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Blood Sweat Tears and Grease => Projects => Specials => Topic started by: goodoltup on Feb 04, 2018, 12:30:08

Title: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:30:08
I'm embarking on a project that I've had in mind for a long time, and finally have the funds to start. I want to make a bike that I would like to ride. A classic bike, with a standard riding position. A modern bike, with disc brakes and good suspension. A fast bike, but with torque and low end power. A bike that does not exist yet, or at least not one that I am completely happy with. I also kind of want to make a custom bike as a protest against some of the trends that see and dislike, such as uncomfortable seats, missing fenders, and rear brake lights that no one can see. I want to make a safe and comfortable bike, too. Are you with me?
A little about me.. I've been riding for 20 years, but not the whole time. I went to MMI in the early 2000's and worked as a Honda mechanic in LA for a few years. After that I switched to small engines and did that for a number of years. Now I am a mechanical engineer, and I live in England. The company I work for makes hermetic connectors for aerospace and military applications, and I am very happy doing what I do. I currently ride a 1976 Honda CD175, but have owned CB550s, CB750s, an XL350, a CB350, and a Suzuki SV650. I am mostly a Honda guy, but that SV650 was just a dream to ride.
I chose the CB550 frame because it has the classic looks that I want, and I am most familiar with Honda. I chose the KTM 690 because I like singles, and because it's a street bike, the engine will have a proper alternator, neutral light, electric starter, etc. I was considering using a CRF450 engine just to keep it all Honda, but I would have to compromise on some of those things.
Lets begin!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:32:07
This is my garage and workspace.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:33:23
I built the workbench specifically for this project. In this picture it's not completely finished, and I am still organising my wrenches.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:35:39
Here is the KTM 690 donor bike. It was cheaper to buy the whole bike than to buy the engine, injector, harness, etc. Plus, I get the handlebar controls, rear brake master, rear wheel, possibly front wheel, and lots of other parts. What I don't use will be sold off.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:37:07
I bought the bike and had it delivered, it came the next day. I had most of the covers and tank stripped off that weekend.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:38:22
Stack of parts to be photographed and put on eBay.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:40:41
Engine ready to come out. My wife's scooter is in the background.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:42:28
And the motor is out!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 12:45:47
I did some work on the bench here. I put up plywood to hang wrenches and things on. I will put some cabinets up top when it warms up a little. It has been like 0 degrees F for weeks, and I can only spend so much time out in the garage right now. I need a heater!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Tim on Feb 04, 2018, 12:54:36
This is a crazy idea - gotta keep watching!

Nice little work space.  Inspiring me to go clean up my garage but not till it warms up a bit more.  In England, with 220v all over the place, can you get a decent electric heater in the shop?

Here in NA (Canada for me) of course everything is 120v unless you run a 220v circuit specifically for things like welders, dryers, heaters and whatnot.

How does it work in England?  I'd expect for higher amperage draws there would be a different outlet style and naturally heavier gauge wiring to avoid plugging a welder into the outlet for a TV.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 13:16:47
This is it, the beginning of my dream. I bought a 1977 cb550f frame from a nice guy up in Essex. The engine more or less fits in as I expected. The swingarm pivots will be removed from the 550 frame and new ones constructed that move the engine a few inches forward. A new swingarm will have to be constructed, as well. I may have to modify the left hand tube under the engine to allow it to come down a little, it sits a little high right now.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 13:22:24
The other side.
On the shop heaters, I might get a propane one and leave a window open. I had one with electric coils in it, but it was weak.
The plugs in the UK are huge, they look like the ones for dryers and welders back home. Most are 30A though. The British are very proud of their plugs, because of all the safety mechanisms like the on/off switch on every outlet, and the automatic gate that covers up the holes when the plug is removed, but it means that even a small USB charger is way too big to put in your pocket.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 13:26:50
Another picture of the frame. I still have some work to do on the frame, like freeing up and removing the centre stand.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 13:28:32
The wiring harness. This entire thing has to fit in the CB690 somehow! There is a ton of stuff on it. Tip-over sensor, barometric sensor, two different computers, just lots and lots of connections and switches.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 13:31:35
Just an updated picture of the workbench with wrenches all hung.
That brings us up to the present! I will try and post every week, as I will be doing work on the weekends. I expect the whole build to take about a year and a half.
Next steps, removing tabs and swingarm mounts from the frame to get the engine situated, and mockup of the new engine mounts. Then the swingarm construction.
Stay tuned!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jpmobius on Feb 04, 2018, 13:59:23
I'm in!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 04, 2018, 18:25:34
Just overpaid for a seat on eBay. I need it for the mockup, I'll refoam and recover it later. The pan is in good shape which is the most important.
This is from a K model, and I don't actually know if it will easily fit on the F model. We'll find out when it arrives, these pictures are from the auction.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: WhyNot on Feb 05, 2018, 07:27:04
I like it.

Gotta watch, seems interesting.

Good looking work space, as Tim said above, inspires me to go clean my spot up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Feb 05, 2018, 08:16:19
Cool project, best of both worlds, classic and modern. Looking forward to this one...
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on Feb 05, 2018, 10:29:12
I like it so far.  Good stuff.  Looks like you lucked out with counter sprocket level.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 05, 2018, 16:26:36
Thanks guys. I agree on the sprocket level. The motor is pretty tall, but the sprocket is situated high as well, allowing a lot of the motor to tuck down between the frame rails.
I also just bought a tank on eBay, a GT550 tank. I really like the lines, and I like the pop up cap. I am concerned that the Cb550 backbone will interfere with the tank, and I'd rather not do any tank fabrication, but I bought it anyway. This weekend I will probably be able to mock up the motor, tank, seat, and radiator.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: canyoncarver on Feb 05, 2018, 18:45:13
Well then, this is interesting.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: spotty on Feb 05, 2018, 19:15:43
^^^^^hey tim, not sure about england (can't remember) but in australia, with 240v just about any plug takes anything, i can plug my welder into any household outlet

nice work going on the bike here too though thats not a nice thing making the missus ride a scooter, surely you like her more than that.....
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Hurco550 on Feb 05, 2018, 19:16:58
I like this thing alot. So cool.

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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: 1fasgsxr on Feb 05, 2018, 19:39:22
This is going to be sweet!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: ridesolo on Feb 05, 2018, 19:56:35
Nice start.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: TranceMachineVienna on Feb 06, 2018, 03:20:12
Im in Sir!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Aussie Steve on Feb 06, 2018, 11:54:04
I foresee a problem.. where is the second one for me to buy? ;)

Really sweet project!

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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: 1fasgsxr on Feb 06, 2018, 13:08:23
What kind of fuel pump you plan on using?
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 06, 2018, 16:26:20
I appreciate the enthusiasm!
I was thinking about using a fuel pump as shown below, just an aftermarket outside-the-tank type. I would like to retain the stock KTM fuel level sensor, however, but that will need a tank modification. Maybe I'll add that capability later.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: dakine_surf on Feb 07, 2018, 19:53:38
Ambitious!!!

I like it!

What is your plan for suspension?  Are you going to try to retrofit the  ktm bits?  Ill be watching


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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 08, 2018, 13:46:07
Cheers Dakine!
I am considering;
     Front suspension
              GSXR forks, with cognito hub and other bits
              Shortened KTM forks, with KTM hub, wheel and brakes
     Rear suspension
              Fox twin shocks, with FZR 600 swingarm (modified to use the swingarm bushing in the engine case)

The KTM swingarm is too long, even if I move the motor forward as far as I can. I will still give it a try this weekend and see how it looks. Even if it does fit and doesn't look to bad, I would have to sub out the aluminium welding to get the shock mounts on, whereas the FZR swingarm is steel. Something to consider.
The KTM forks need to be shortened by 100mm if I have any chance of using them. I have not investigated yet if this is possible, but soon I will disassemble one and see what needs modification.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: dakine_surf on Feb 08, 2018, 14:51:05
100mm is about 4 I dont know the duke suspension travel is but I feel like 100 mm is doable. 

If it were mine Id probably keep as much of the ktm stuff as possible, just for the cool factor...  but also keep with the twin shock theme out back so fzr swingarm sounds like the way to go.


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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 10, 2018, 11:40:42
Here is the start of mock up. The tank ALMOST fits, but the tunnel will need to be modified to clear the frame spine. That will allow it to sit a little lower and line up with the seat.
I also put the KTM triple trees on there just to see how it might look. The KTM steering stem is much longer than the CB neck, but that might present an opportunity. What if I were to lathe up some bearing cups that could be fitted to the CB frame? That way the length could be matched, and the KTM bearings could be used, with no need to make a new steering stem at all. Provided I can shorten the forks by 100mm, all KTM components could be used for the front end. This will be seriously considered. A GSXR front end would really look nice, but the KTM front end would be much cheaper and need almost no modification.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on Feb 10, 2018, 13:39:58
I did a similar mod.  No reason not to, as long as the front end works with your frame geometry.

(http://uploads.tapatalk-cdn.com/20160314/1d96bcd8597d10fa7240c78209633207.jpg)

(http://uploads.tapatalk-cdn.com/20160314/4413f6bac343d7d524493e0595b1785c.jpg)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 11, 2018, 04:53:43
^^ Hi Irk,
That is very helpful, thank you very much! I will first measure the KTM clamp offset and determine if I can shorten the forks, and all being well I can make the cups on the milling machine at work.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: SONIC. on Feb 11, 2018, 17:27:36
I like it!

Just for curiosity sake though, why use the flexy old cb frame? Why not swap the swinger and modify the ktm frame for the look you're after?

Granted I'm not familiar with the frame layout, but if it were me I'd probably keep the ktm frame and lop off the subframe and rebuild as a twin shock if that's the look you're after
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 11, 2018, 17:44:57
^^ Hi Sonic,
I can't say that the frame isn't a concern, but I won't be riding it at 100% anyway. Using the KTM frame would be too much 'making a modern bike look classic' and not enough 'stuffing a hooligan motor into a classic bike.'
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Feb 11, 2018, 20:15:30
I like your project and I get the ''classic bike with modern motor''. The closer the swing arm  pivot is to the sprocket the better, from the mock up it looks like you will have to mod the frame a lot. Also is there enough space for the throttle body & air filter? Good luck I will be following with interest. I like the tank
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Kanticoy on Feb 11, 2018, 21:08:51
Very interesting! Ill follow along!


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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: CrabsAndCylinders on Feb 13, 2018, 18:49:57
I like it!

Just for curiosity sake though, why use the flexy old cb frame? Why not swap the swinger and modify the ktm frame for the look you're after?

Granted I'm not familiar with the frame layout, but if it were me I'd probably keep the ktm frame and lop off the subframe and rebuild as a twin shock if that's the look you're after

I was wondering the same thing.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 16, 2018, 07:32:58
A proposed solution for the headstock is shown below. There is not a lot of room in the Z direction to allow for bearing cups, so some compromises may have to be made. In the second two pictures the CB headstock is shown in brown. The KTM bearing is shown in black. The bottom bearing cup is relatively straight forward, it locates in the original CB bearing diameter and would be welded in place. The top cup is more troublesome. There is not enough room to make a diameter that centers in the CB cup, so it locates on the outside. A spacer, shown in blue, sits in the original CB cup and provides a bottom surface for the KTM bearing, shown in black, to sit on. Like the bottom cup, the top cup would be welded in place.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: john83 on Feb 16, 2018, 19:19:12
Very cool stuff!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 18, 2018, 12:59:47
Did some more mocking up of motor in the frame. Some compromises had to be made to make everything work. I didn't want to cut the frame rail, but the alternator cover is just too low. It would push the injector right up into the frame, and the right hand side of the engine would look like it was floating way above the frame rail. So, I cut the frame rail so the motor can sit down in the frame. Something will have to be devised to reconnect that frame rail, I might make a new frame member with a bender to clear the alternator.
The injector just about clears the frame. I will have to machine a new fuel inlet, the original one was removed for the second photo. The original fuel inlet was just too tall.
The new swingarm plates will locate the pivot 70mm forward, and 12mm down. I have mocked up the plates in cardboard, and tomorrow I will CAD them up and start sending out requests for quotation. I would like to get them laser cut if possible, thickness of plate to be determined. 10mm maybe? Too much?
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Feb 18, 2018, 19:08:23
Have you thought about bolting your new mounting plates to the inside of the existing plates? It is would make installation and alignment very easy. Apologies if this is what you always intended.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 20, 2018, 01:59:14
^^ Hi Pete,
You are right, it would be easier and more efficient to make plates that fit on the inside, or the outside, of the original mounts. But I would be concerned about any movement allowed by the bolt-plate interfaces, I think a weld would be more secure. I guess you could weld the plate to the original mounts, but all in all, I think it would be more attractive to make new mounts and have them welded in.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Feb 20, 2018, 04:29:59
^^ Hi Pete,
You are right, it would be easier and more efficient to make plates that fit on the inside, or the outside, of the original mounts. But I would be concerned about any movement allowed by the bolt-plate interfaces, I think a weld would be more secure. I guess you could weld the plate to the original mounts, but all in all, I think it would be more attractive to make new mounts and have them welded in.

Very true, it would look a lot more professional making the whole new mounting. Great project, by the way, looking forward to seeing the end result.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 22, 2018, 11:18:34
Moving ahead slowly. I got quotes from tube benders for the frame member that will be welded in place to clear the alternator cover. I also got quotes on laser-cut and water-jet swingarm and engine mount plates. All very reasonable.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: XS750AU on Feb 23, 2018, 04:57:12
Hi, if you don't mind sharing. What do you consider as reasonable?

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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: hooligan998 on Feb 23, 2018, 07:33:44
Very interesting project.  I'm in.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Rat_ranger on Feb 23, 2018, 10:30:12
Around washington it seems to average around $60hr for waterjet. 
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 05, 2018, 12:09:48
^^ XS750AU,
I received quotes for the following.
Laser cutting, qty 2 swingarm plates in 10mm, qty 2 engine mounts in 6mm, 95
Water jet, qty 2 swingarm plates in 10mm, qty 2 engine mounts in 6mm, 44
Frame tube, qty 2, 75, PLUS VAT
Frame tube, qty 2, 54.26

This being the case, I believe I will buy the water jet frame parts, as I am not concerned about the draft angle. The frame tubes are both the same, so I will buy the cheaper of the two.

Lots of snow here in England, maybe this weekend I will be able to get out to the garage and do some work!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: XS750AU on Mar 06, 2018, 03:53:19
Those prices are much better that we would get down under. Very reasonable.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 01, 2018, 11:58:21
I have returned from a business trip in the US and am ready to get back to work. Still cold here in the UK though. Even if you can get the garage to a good temperature, all the tools and anything metal remains cold to the touch, and it really soaks into your hands. In the first picture, my boss has gifted me a heater, the type with a large electric coil in it, like a big hairdryer. I will put that up in the shop somewhere and duct out of the outlet and try to direct the air around properly.
Also in the picture is my new air compressor. Super cheap, but it is 10 bar and 14 cfm. Problem is, all my air tools have Milton Type M fittings, shown in the second picture. These fittings are 1/4" NPT, so I can't just go and replace all the fittings, as the fittings sold here are 1/4" BSPT. SO, I had to order a Milton Type M quick connect from the US, and I will use an NPT to BSPT adapter to put it onto my hose. A trial of the air compressor must therefore wait until I receive that.
Third picture is just a reference of how the garage is shaping up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 01, 2018, 12:08:49
So I've been thinking about it, and I welcome people's opinion on this. I have to remove the original swingarm pivots, in order to move them. The only way I can see to do this would be to fixture the frame in a jig, align it with reference to the original pivots, then the pivots can be removed and the new ones welded in with reference to the jig. I figure I can make a frame jig fora couple hundred GBP, it just seems like a lot of work to go through for one operation. I could reuse parts of the jig to construct the swingarm, but a lot of it would never be used again. Is there any other way to do this?
I bought a swingarm from an FZR, hoping that maybe I could modify it work on this project. Upon inspection, however, I think it would need heavy modification in order to straddle the swingarm pivot bushing in the 690 motor, with the construction of new bearing assemblies on both sides. And, it would need some kind of solution for the axle, and the length and diameter would be different. I think maybe that I will just make a new swingarm from scratch out of tube or box section. Not sure yet.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jpmobius on Apr 01, 2018, 13:47:56
I think there a couple of important issues to consider here, as usual they are competing difficulties.  First, as you have touched upon, is the original pivot point in relation to the engine.  The ideal pivot would be concentric with the output shaft/countershaft sprocket.  That of course is to make life easy for the drive chain.  This is very complex/expensive to implement manufacturing wise, so engineers place the pivot as close as practical that center.  There is an additional strong benefit to having the pivot actually be part of the engine case, as all the loads can pass directly (more or less) into the swing arm and not have the engine mounts/frame work as a middleman.  While moving the pivot back behind the sprocket center is undesirable, it's not too bad if it is very close and the arc the arm passes through is small, which brings up the second point.  Moving the pivot further back, say where the original frames swing arm pivot is, places it quite a ways behind the sprocket, and the resulting change in chain tension as the suspension works becomes unacceptable.

Moving the existing frame pivot forward also creates some issues.  If you move it to align with the engine pivot, you will be rather a long distance away from the existing frame.  That places the loads input from the swingarm on the end of a much longer lever and will likely add flexibility to the system, though how much and how real world important is hard to tell.  Increased likelyhood of vibration fatigue cracking also becomes something to consider.  Swing arm pivots are placed as close as possible to the frame structure for a reason - look at the originals.  Certainly relocating so far away will add some weight, but being coincident with the engine pivot would definitely be a plus.  Personally, I would have the aesthetics in mind as well - I think a lot of flat frame real estate in this area is not too desirable.

Discounting other issues with moving the engine back (fitment, weight distribution), you would ideally align the engine pivot with the frame pivot and alter the swing arm to fit in between.  Looks like you have spent some time figuring out where it is now so moving it may not be practical.  Also, looks like there is enough distance here to consider the wheelbase and tire clearance with potentially moving the swing arm so far forward.

If that is the case, I think the job will not require any sort of major frame jig.  Get the engine aligned exactly where you want it and mount it so you can get the swing arm fitted to it.  I've made temporary mounts on occasion.  Probably less trouble than you expect to fit the swingarm.  The thing to remember here is that swing arm rotates on a fixed, solid, structural frame element comprised of the through bolt, inner bearing races (or bushings), any sleeves or spacers (including the engine) and the two frame elements.  The swing arm is captured by these components and shimmed or otherwise fitted to eliminate any play.  With this in mind, and with the swing arm fitted to the engine and the engine in place, you only will need to build structure between the new frame mount and the existing frame.  I would think you could get this all mocked up with the existing swing arm mounts still in place, and use them as a benchmark to ensure all the new work is properly aligned.  Once you are certain everything is lined up, you can remove all of the existing swing arm mountings and simply tack weld new structure in its place.  Take the engine back out, put the pivot bolt and bushings, sleeves etc back in and tighten it down.  In your case, you probably will have to make a long spacer to replicate the engine, any spacers and bearings in the actual assembly.  With a bit of care you should be able to finish weld everything with out too much trouble.  There will be some distortion, but no more than you would suffer with a complete frame jig.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 05, 2018, 14:33:41
Hello jpmobius,
Thank you for your input, that gave me a lot to think about. I just quickly made a CAD model of what I think it is you are talking about. The frame in the model is CB400F, and the motor is a KTM 525, so it is representative only, this is not what my bike will look like. To be honest, this combination looks like it would actually work better than the 690 engine, but that is the engine I decided on!
- Image 1 shows the engine in the easiest position, no frame modification required. The swingarm pivot bolt goes through the engine and the swingarm. The swingarm would have to be constructed to straddle the engine bushing in this case. On the bike that I am building, I'm not sure this is possible, but I will check again. It does leave a LOT of space between the motor and the front frame downtubes, and it looks kind of funny. Also it positions the motor pretty high.
- Image two shows another possibility, which is the motor mounted forward of the original position. In this case, the original swingarm pivot would still be utilised, but the swingarm pivot bolt would no longer go through the motor swingarm bushing. This could make some undesirable geometries with the swingarm and chain. The original swingarm could be used in this case.
- Image three shows what I was thinking, which is positioning the motor forward a bit, 70mm, and creating a new plate that would be welded to the frame.

I will try and see if I can move things around and mockup the motor per Image 1 and see if looks alright.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jpmobius on Apr 05, 2018, 18:14:39
If you still have the KTM swing arm, you can determine where the engine sat within the KTM wheel base and compare that to your new project .  I think that would be a big driver to help me decide where I wanted to locate the engine in the Honda frame if this were my project.  I would expect the KTM  to have steeper steering geometry and a more forward center of gravity that you will have a hard time reproducing in the Honda chassis without - well making it into more of a KTM chassis than a Honda and thereby spoiling the retro look I assume you are going for.  You have said the KTM arm is too long.  Can you say why?  I get the aluminum being a stumbling block if you don't have the capability to do the fab work, but it might be worth comparing those difficulties with those generated by using an alternative swing arm.  I am sure it would be quite long (and in general I don't like increasing a bikes wheelbase), but if you decide to move the engine forward to the current proposed location, how much too long is it?  Is it viable to move it forward to resemble the KTM's engine location?  That would certainly make the swing arm length ok (at least if you ask KTM!), but it might not be practical or good looking for your application.  That could also potentially cause a lot more surgery of the frame at the swing arm pivot,  but at least it would all be in steel.  And of course there would be at least some aluminum fab for the rear shock set up, but that would likely be fairly painless.  Certainly the swing arm is plenty robust for the twin shock conversion so all you will need is the actual shock mounts.

Apologies for adding complexity to a pretty straight forward endeavor.  I personally find it easier (not to mention cheaper!) to think a little more about something before having to build it (over!).  And, at risk making things worse, it is none too early to consider the overall balance you are shooting for, and getting comfortable with the compromises you will have to endure.  Since you are keen to end up with a bike you like to drive, keep in mind the limitations of the chassis you are using.  The Honda frame will thank you for retaining the twin rear shocks.  But be thoughtful when you consider changing the front end.  Most new front ends have very much reduced offset compared to the ol' CB, which will result in a much bigger trail number, which will noticeably slow down the handling which you really do not want, as it isn't exactly a switch blade to start with.  The cure would be to steepen the rake (like to whatever the new front end came off of). That very likely will input loads very much equally, if not more so disliked by the Honda frame than the reduced offset, not to mention adding all sorts of additional fabrication/design work.  (noting how ultra rigid the KTM steering neck to swing arm pivot connection is exactly like the Honda's is not!)  So consider keeping VERY (read identical) similar offset in the triples, similar wheelbase and weight distribution (read engine center of gravity - if you live long enough, I DO get around to the point!) if you want to end up with a bike with similar manners as the 550 - not a bad thing at all!  I'd bet if you keep the stock steering geometry and focus on the suspension itself and keep the wheel widths reasonable you will come very close to hitting your bulls eye for building a great driving "old" bike!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on Apr 05, 2018, 20:49:01
Don't forget carburetion and air cleaner locations, too.  Where it sits in the frame, forward and back especially, effects both carburetor and exhaust.  It's always fun to be forced into trying different carbs based on how and if they fit into the frame.  My F650 was a special kind of puzzle to find a good carb upgrade that also fit into it's wishbone frame.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 01, 2018, 17:08:51
Ok time for some updates. I bought a Tig welder and have been using it for some projects. It came from Amazon and it was very cheap, 250. In fact, I bought one and received it, and right out of the box it was broken, LCD screen would not light up. But, upon reflection, it was the right model for the right price, so I decided to go ahead and buy another one despite the first one being bad. I received the second one, and it works great. It has a dial on the front where you can dial in the starting amperage, the ramp rate, welding amperage, ramp down rate, final amperage, etc. It really works well. My first project, after some initial testing, was welding some new mufflers on my CD175. I got some aftermarket slip on mufflers, but the diameter of the new muffler was 8mm larger than the head pipe, so I used the lathe at work to machine up a spacer. Then I welded the spacer to the head tube, and the muffler to the spacer. Came out real nice.
The welder will be used in this CB690 project to create the frame jig, weld frame tabs and things, and maybe even fab the swingarm.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 01, 2018, 17:18:44
Work has begun on the frame jig. I have received several metres of 2x3" steel box section tube, which will form the frame of the jig. Instead of clamping it all together like some frame jig kits I have seen, I will weld it. One problem I needed to solve was making the steering neck cones for the jig. I decided that instead of making cones I could use the existing bearing cups. First I make some discs on the lathe. The bearing cups were then ground down to allow a light fit in the steering neck cups. The bearing cups were then tig welded to the discs. The third picture shows the welded assembly in the steering head. The welded assembly then went back on the lathe to have a 16mm hole drilled concentric to the bearing cups.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 01, 2018, 17:25:30
I used the mill at work to get the required angle on a small section of the tubing, and to drill the 16mm holes through both sides. The small bit was then welded to the frame jog upright, and 16mm threaded rod used to make the steering head holder. I don't have a lot of great pictures of this process, but hopefully from the last picture you can see the bit that was in the mill.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 01, 2018, 17:28:43
And the garage is looking pretty good! Soon the frame will be in the jig and the work of putting the motor in can begin.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: stubsryan on Jun 03, 2018, 09:26:42
Sweet project mate. Im really looking forward to seeing how this one pans out. Keep up the good work


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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: CrabsAndCylinders on Jun 03, 2018, 16:20:55
Very nice workshop!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 09, 2018, 17:21:17
This is my current welding setup. I ran a higher amperage line to a socket that is only used for the compressor and the welded. Only one at a time can be used, but that really should not be a concern. The welder has been doing great, I have no problems with it at all. It's a lovely piece of kit, cheap and cheerful.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 09, 2018, 17:30:56
Ok this is what it's all about. The frame is in the jig. I used a digital inclinometer to ensure that all the tubes were square to each other and that the headstock was set at the same angle as the stock KTM. This was really just for mockup, the real headstock angle will be set with the shock length once the frame is released from the jig. For the time being the most important thing is that the headlock is perpendicular to the jig, and that the frame is centred in the jig. Once all the measurements had been taken, the frame was tacked on the upright that is under the frame cross member. Next I will make a holder for the engine so it can be positioned in the frame while being kept in the same plane as the headstock. Then it can be positioned and the motor mounts mocked up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 18, 2018, 18:17:04
Here I've made an engine mount out of some tube and remnants of the KTM skid plate. This allowed me to position the motor in one plane, moving it around until it worked. There were several compromises to make, namely if the motor was too high the injector interfered with the frame, and if it was too low the chain would rub on the frame cross member. A pretty good solution was found, in that the injector could be rotated a few degrees to allow the necessary injector clearance, and the motor could be positioned at max height and provide good chain clearance. Still necessitates the replacing of a frame tube, but that I was prepared for that, see a few posts ago where we priced up a precision bent tube.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 18, 2018, 18:19:57
Mockup of the tube and swingarm plate. I know the plate is big. But it is the compromise I am comfortable with.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 18, 2018, 18:24:50
This may be a big decision here, but I think I can use the original KTM swingarm. Think of the work it would save! I wouldn't have to manufacture a swingarm from scratch. The bearings would work, the rear axle would fit, it looks cool. Only problem is that it taking into account the 75mm the swingarm pivot is moved forward, the KTM swingarm would add 80mm to the wheelbase. And, of course, it's mono shock and not dual shock. I believe that I can have some clevises welded on (I won't do it) and I can machine off the boss for the mono shock, that should be trivial. The rear calliper would have to be mounted differently because it would interfere with the shocks, but again that is ok. I think I can live with this.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: JustinLonghorn on Jun 19, 2018, 08:42:21
Righteous work so far.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Jun 19, 2018, 09:54:34
I like it. Moving the SA pivot forward and using the KTM SA is a good solution, keeps the pivot point close to the sprocket. I think the KTM SA looks great too
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 08, 2018, 13:55:20
I took the forks apart in preparation for shortening. Minor panic as for a couple of days I thought that they could not be disassembled far enough to replace the topout spring, but after searching the internet for pictures I did notice that there was a hidden snap ring that allowed them to come apart. I will be ordering a spring kit that shortens the forks but maintains the correct spring rate. Also new seal kit, of course.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 08, 2018, 14:00:58
Finished mocking up the tube and the motor mounts. The left motor mount is shaped so that it matches the shape of the stock sprocket cover. The right side one looks more like a simple triangle. The swingarm mounts will be made in 10mm plate, the front motor mounts in 6mm plate, all waterjet. The tube will be formed by a specialist mandrel bending company.
Also, I bought a cb550 tank. I like the gt550 tank better, but it would need tunnel modification in order for it to fit, and in order to keep this project running I thought it would be a good idea to minimise unknowns and potential problems as much as possible. I will keep the gt550 tank and maybe add it later for version 2.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 08, 2018, 14:03:17
My manager gave me an engineering drawing of an automatic transmission. It has hand written notes and a date from 1968. I'm very thankful, it makes a nice addition to the garage.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: snowEH on Jul 26, 2018, 17:46:51
awesome project cant wait to see more progress !

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Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: JadusMotorcycleParts on Jul 28, 2018, 07:58:18
This is awesome!  I'm in!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: john83 on Aug 19, 2018, 22:30:54
Nice work! It's looking cool.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Aussie Steve on Aug 20, 2018, 12:36:12
Any exciting updates to share?

Sent from my Lenovo A6020a40 using DO THE TON mobile app (http://r.tapatalk.com/byo?rid=89466)

Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Aug 22, 2018, 17:23:03
Hi, yes, it's been too long since I've done any real work on the project. I wasted a lot of time getting the CAD files for the plates and tube, and wasted more time getting them quoted and ordered. I have now, however, received the plates from the water jet company. I ordered a few extra just in case I make a welding or grinding mistake. I sent the DXF files with a PDF drawing of the part with dimensions, but the water jet people just loaded the DXF and started cutting, not realising it was scaled 2:1. You can see in picture two that the front motor mount plates are huge, twice as big as they should be. The water jet people recut them and sent them out next day, so no harm done.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Aug 22, 2018, 17:28:22
Started making the swingarm pivot mounts on the manual lathe at work. The finish came out a little manky, but that is due mainly to speeds and feeds. These will be welded into the plates and will use the stock KTM swingarm hardware to link up the engine, swingarm, and frame. The last picture shows the threading operation. I also have to fab up a tool to torque the swingarm pivot insert, more on that later.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Aug 22, 2018, 17:31:11
Slow going on the frame modifications. All those factory welds have to be ground down and the tubes prepped for welding. I've used a combination of an air-hacksaw, angle grinder, and small pnuematic grinder with sanding discs. Not looking forward to having to finish this up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Aug 28, 2018, 09:53:20
A drawing of the swingarm pivot that I machined. Inspection of the part showed that I got within 0.05 mm on most dimensions, some bang on, with the exception being the depth of the bore. That was way out. I used a stop on the lathe to gauge depth but something wasn't right, ended up being out by 0.8 mm. For this application it is not important, just need more practice on the lathe.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Aug 30, 2018, 13:41:41
This tool my colleague made for me on the mill, to torque the swingarm adjuster nuts that are located in the pivot. It has a 17mm hex.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on Aug 30, 2018, 13:52:27
Looks like an oil slinger socket.

(http://thmb.inkfrog.com/thumbn/permile/MXE0002_(5).JPG=450)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Sep 23, 2018, 11:56:31
It's looking good. I have assembled the swingarm pivot components and will start welding soon. The plates have to be fettled with the grinder until they fit perfectly, and v-grooved. Also the front motor mount is complete. The spacers are made of mild steel, I may weld them to the mount plates for extra rigidity. Also those bolts will be shortened in the lathe. They were chosen to give the proper amount of unthreaded area.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Sep 23, 2018, 13:02:41
Have received the frame tube from Pipecraft. I paid 90 for two, and they sent four. They I haven't measured them, maybe two of them are close but not conforming to drawing. I don't really need four, but maybe I can use them for weld trials.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Oct 10, 2018, 03:46:56
Sneak peak. I ordered new aftermarket sidecovers and seat for purposes of mocking up. The sideplates have been tacked in only at this stage.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Oct 10, 2018, 13:30:28
Oh yes! Great rear end  :)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Nov 04, 2018, 15:19:10
Time to choose my rear shocks. I would like to have the shocks in hand for mocking up the mounts that will be welded to the swingarm. Not being sure what length shock to buy I made a calculator in Matlab where I inputed frame dimensions and proposed shock and fork lengths, and get the resulting rake, trail, swingarm angle, shock angle, and seat height. I had targets for all 5, so I fiddled with the front fork length and shock length until everything was satisfied. I will start with a 320mm shock, taking into account the height of the shock mounts themselves. This is with shortening the front forks about 50mm. This can all serve as a basis, and once the bike is rolling I can adjust the front fork length with springs and spacers, and the rear shocks are +-10mm adjustable, too, so I can fine tune it. I could have done this in 2D cad, but this was a fun project. Screenshot 3 shows the program output.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: doc_rot on Nov 04, 2018, 15:40:26
just caught up with this. Nice work.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: LMCol on Nov 04, 2018, 16:21:33
Awesome build, I've always wanted to drop a big modern single into a lightweight street frame too.

Also, major workshop envy..... I need to learn to clean up after myself.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Nov 05, 2018, 07:21:38
Thank you guys, I appreciate the kind words!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Nov 19, 2018, 18:08:49
The swingarm pivots have been tacked to the frame plates. The frame plates have been tacked to the frame. The LH frame tube has been tacked into place. Not shown are the bushings I made to line up the frame tube. I made 2 slugs out of mild steel that go inside the tubes, and the tubes are all then plug welded through 6mm holes. All this will allow me to remove the frame from the jig when necessary, it is not longer needed. For now it stays in as I continue with the shock mounts and some other frame tabs, but the alignment between the headstock and swingarm pivot is locked in. When the frame comes out of the jig I'll take it to a welder to finish up and cover over my tacks.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jpmobius on Nov 19, 2018, 19:48:57
That's all looking very nice!  Those are some beefy mounts.  Beefy is good.  I think you can safely bore a couple of holes in the swing arm/engine mounts to lighten them up a bit visually.  They may take up a lot of real estate visually, but I think you made the right decision from an engineering perspective with the factory arm and pivot location.  Nice work on the lower frame tube as well - everyone will think it is factory when you are done!  Keep an eye on your trail number - nervous bikes are not fun to ride!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jpmobius on Nov 19, 2018, 22:24:53
When the frame comes out of the jig I'll take it to a welder to finish up and cover over my tacks.
Looking at the pics, I'd bet your gas welding skills are up to the task.  If the design is good, it doesn't rely exclusively on the welds, and yours is.  You'd likely be able to do a good job brazing the new joints.  Lots of gusseting/surface area involved in brazing compared to welding, and done well, the connection is super reliable.  Worth considering - a lot of the point in doing it at all is doing it yourself.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Nov 21, 2018, 10:50:25
Thank you jpmobius,
It was actually tig welding you see there. I'm not sure of the penetration I got on those, and I was concerned about the heat buildup on the frame, as evidenced by the blueing. My technique needs work, and I move kind of slowly and the heat builds up.
The plates are 10mm, which I am hoping is enough. But they are quite long, and I think they will need some gusseting in the perpendicular axis to keep them from flexing. I think I will mock up some triangular plates to tie them into the frame in that direction.
I read your forum entry on the RD, I like the result very much. Did you use YSS shocks? I have some purchased and ready to mock up, just wondering if you like them?
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jpmobius on Nov 21, 2018, 17:52:18
Well, just make sure you let the work air-cool.  Definitely getting a lot of heat in the weld area, but that shouldn't be an issue as long as you don't make things brittle by quenching.  10 mm is very robust. I think everything is ok as is and adding additional gussets probably won't be of a lot of benefit.  You could potentially add a bit of stiffness by doing so, but I doubt if you would detect any benefit when you ride it.  Accurate fitment of the spacers in the front and good fitting fasteners all around will likely will prove more helpful.  The rear mounts with the swing arm pivot incorporated into the back of the engine case is about as good as it gets. The weak "link" in fabrications like this is usually in the connection to the tubular portion.  You have to have fairly frail brackets or mounts for them to give up before the connection to the frame.  Look at any factory design and I think you will note that mounting anything including the engine, is accomplished with comparatively thin stamped sheet metal components.  Heavily loaded mountings are often made in two thin pieces and weld to the two "sides" of any tube instead of the center.  Single element brackets also attach to the side in most cases as well.  This is because (depending on the direction of the load) doing so spreads the load out in a larger, friendlier area on the tube and reduces the likelihood of fatigue cracking in the tube.  This is usually much more catastrophic than cracking the bracket, and consequently you see cracked brackets more often than cracked tubes due to this design preference.  In your case, the rear mounts are very strong, and will feed all the loading into the original frame tubes.  Unfortunately, the result is that there will be large forces at the ends of the plates where they meet the top of the tubes.  This is the place where it is much better to have a bracket design that attaches to the side of the tube rather than the center, because the tube can "move" a lot more in this area when loaded in this direction which is easier on the material.  Or in other words, the load is in effect spread over a larger area even if the weld is exactly the same size.  So down the road you would be wise to keep a close eye on the tubes for cracking at the ends of those big mounting plates.  This of course would be the likely location of trouble even if you did design the mounts for welding to the sides of the tubes as well, just less likely.  Not trying to raise alarm here, just advising you keep an eye on these areas as the miles rack up.  The good news is that steel is nearly universally used for good reason.  All steels have a fatigue (aka endurance) limit.  That means that if you don't load or cycle your load beyond a certain threshold, your design will last indefinitely.  Exceed those values and your design can be relied on to fail in (hopefully) a predictable way.  Materials with no endurance limit (like aluminum) will always eventually fail, no matter how kindly they are treated, so you have to be very careful to decide what an acceptable lifespan will be.  Hopefully in your case, your design will be on the "good" side of the curve and you will live happily ever after - just keep an eye on things!  This would be a good (I think I mentioned this previously) place to braze the joint.  This is good because the fillets made with brazing will be much larger than welding and spread the load over a much larger area.  Additionally, (with sufficient skill) the steel will be heated to a much lower temperature which will not disturb its original mechanical properties.  You can braze with your tig torch, but as you are still getting acquainted with using it to weld, I suggest that you weld both sides of your plates, but do NOT weld the very ends.  This will spare the tube from getting so much of a stress riser in the center, and move those loads into the end of two welds, one on each side.

Also, as a guess, maybe you are not using enough power when welding.  This may be counter intuitive, but the logic is this:  The quantity of heat you place into the material is a combination of energy and time.  Too little energy takes too long to build up enough heat to start welding, so a much larger area is heated up very strongly.  Turn up the amperage, and the weld area melts very quickly, allowing you to weld and keep moving the heat impacted area forward and allowing the just welded area to start cooling - net effect is less heat injected into the parts.  Aside from the gas shield, that's the great value of tig welding - speed and less heat.

The shocks on the black RD are from Race Tech and built to order.  I don't have any personal experience with YSS.  Very highly recommend Race Tech if you want to upgrade down the road.  They don't sell you what they have, they determine what you need and build it for you.  Results are exactly what you would expect.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 01, 2019, 11:09:21
I made a temporary upper shock mount for mock-up purposes, here it is held on with a G clamp. Once the lower mounts are made the top mounts can be finished and welded in place.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 01, 2019, 11:10:35
Another view. YSS shocks are roughly in place.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 01, 2019, 11:18:52
Mocked up the lower engine mounts. These will be tacked up so the motor can be removed, so they can be properly welded in. Had to lay the frame over to get them mocked up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 01, 2019, 11:28:01
Off the frame jig now, as the swingarm pivots and plates are tacked in, the jig now is not needed. I will use it for convenience only from here on out. I wanted to get the frame off the jig in order to final measure up the steering head and bearings, so the stem can be drawn and ordered. Took this opportunity to do some more frame work. The steering lock was removed and the hole welded up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 01, 2019, 11:31:34
Also removed the cb550 front right motor mount. It came off pretty easily actually, as it was only welded on two sides. My Bosch angle grinder got quite a workout, though. Also removed the cb550 rear fuel tank mount / frame brace. This was interfering with the K&N air filter that I bought for the bike, so I cut it out and will replace it with a custom part later.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 01, 2019, 11:39:04
Quickly made a jig to mock up the footpeg locations. I put the bars, tank, and seat on, and had a sit on the bike. I found actually that the footrest location felt pretty good close to where they were located on the cb550 originally, maybe just a touch to the rear. The footpegs are Honda cb250 or something, the mounts are gsx650f. The aluminium brackets shown will not be used, only the pivot bracket.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 09, 2019, 17:07:43
Swingarm mounts came in the mail today.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Jan 12, 2019, 08:58:26
You've probably thought of this already, but you will really need a good jig (or the swing arm) in place before you finish welding up the swing arm pivot brackets. Great work on the project though, can't wait to see it finished.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 18, 2019, 04:23:21
Late last year I drew up the lower shock mount as shown in the above post. It was quoted by three rapid prototyping machinist companies, and finally produced by a company called Shift.BZ. The cost was around 200 EUR for two, delivery time was less than 5 weeks. As an engineer I typically get 8 weeks for machined parts for our business, so 5 is great. Highly recommended.
Below is a CAD model of the shock mount with the bolts and washers installed. I decided on using a through-bolt instead of a clevis type, because of the distance needed between the shocks would have required quite a weird looking lower mount. The lower mount as machined will be welded onto the existing KTM swingarm. I cut all the parts shown in blue out of titanium on the lathe.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 18, 2019, 04:46:01
Phone pictures of the finished components.
Next, I manufacture the upper shock mounts.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: XS750AU on Jan 18, 2019, 06:36:08
Hi
Question on the Hitbox  TIG200P, is it any good?
Pro's & Con's
Thanks
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 18, 2019, 07:19:35
Hi,
I have no problems with the Hitbox at all. Other than the fact that the first one that I bought was dead right out of the box, it's replacement has been perfectly suitable. I'm a beginner TIG user and don't put that much use on it, so perhaps with heavy use it might struggle, but I don't know. Build quality is acceptable, and no bits or pieces have broken yet. The MMA welding function works fine as well. I'm not totally sure that the tig cups are interchangeable with major brands, that remains to be seen. I'm honestly struggling to say anything bad about it.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: cb360j on Jan 18, 2019, 08:11:50
Only 200 eur is a steal deal! Everywhere near me wants to try and charge $700-$1000 usd for one, or two off prototypes.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 19, 2019, 03:51:07
Pete12, I REALLY enjoyed your thread on the CB450, I will give it a good read through and see if there are some things that you did that I may try on my machine. Cheers!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 19, 2019, 03:54:30
CB360j, I completely agree, the machinists I use for my job would normally charge about 800 for ANYTHING, just to get the machine setup. This company Shift.BZ is network of machinists that bid on jobs when they have spare capacity, so the prices can be lower. The parts don't come with an inspection report or materials certificate, as I would normally expect, but the parts were of very high quality and measured up fine.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Jan 30, 2019, 09:42:25
Pete12, I REALLY enjoyed your thread on the CB450, I will give it a good read through and see if there are some things that you did that I may try on my machine. Cheers!

Thanks goodoltup, but you are doing a great job on your bike, I doubt you'll need anything from me.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jordandogtown on Jan 30, 2019, 16:21:57
I love seeing such an ambitious idea come to life. Nice work man. I'll definitely be following along
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 31, 2019, 16:28:19
Lots of progress has been made, but few updates. Big day! I brought the frame to be welded professionally by a frame builder. He put it on his jig and found that it was tacked up pretty square, which pleased me. All bits that I tacked were welded up properly, including the frame side plates, swingarm pivots, lower engine mounts, top shock mounts, etc. The aluminium lower shock mounts were also welded.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 31, 2019, 16:37:46
I quickly made a better work table out of some scrap. It took about an hour to build, and it's pretty stout. I will likely disassemble and dispose of it after the build, so I didn't spend a ton of effort on it. But it did come out pretty nice. I got a wheel chock so when the time comes to take it off the jig (it's back on the jig temporarily after welding just to hold it) I will have a way to secure it. I will probably put it on the centre stand with the wheel chock during the rest of the build.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 31, 2019, 16:39:24
Some closeups of the welding work.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 31, 2019, 16:46:42
There was some interference with the brake torque arm, so I milled off the ledge on the arm with the Haas at work. It's tough to explain, I should have taken some before pictures. There was a ledge, or overhang, on the torque arm who's purpose appeared to be to keep the arm attached to the swingarm during wheel installation. With it gone it might be more fiddly to get the wheel on, but I don't think that's a huge problem.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 31, 2019, 16:48:54
Made some radiator supports on the Colchester. These bits will be welded together, and the tube will be welded to the frame when it's time to mock up the radiator. May not use these for a while, just had some extra time on the lathe after work.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jan 31, 2019, 16:59:21
Just a couple more mock up shots.

Tomorrow, the steering stem comes in the mail. Soon it will be a roller!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: jordandogtown on Jan 31, 2019, 17:11:33
That swingarm looks so sweet with twin shocks
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 01, 2019, 04:57:29
Made some slotted spacers to affix the footpeg brackets. They will be parted off to about 5mm, and welded to the frame to act as anti-rotation fixtures. I made the tubes on the lathe and manually cut the slot on the Haas.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: JustinLonghorn on Feb 01, 2019, 07:56:43
Nice to see the progress, man! Keep it up!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Maritime on Feb 01, 2019, 10:53:42
Nice work
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 03, 2019, 05:59:32
Yesterday I made the centre stand stop. The cb550 uses a rubber bit on the mufflers to provide a stop for the centre stand while it's in the up position, and I won't have the original mufflers on this bike obviously so I needed to fabricate something else. I used a rubber appliance foot that screws into a tab on the frame, and a corresponding pad welded on the centre stand. It makes a nice, solid, quiet stop for the stand. I did run out of argon while welding though, so I may finish it with a stick.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 12, 2019, 07:21:43
Fuel pump installed. This is the fuel pump from a Honda VT750. I got the idea from some other thread I follow, but I can't remember the poster to give credit. The pump has an integrated filter and pressure regulator, with the output pressure being the same as the KTM. This way I won't have to put all that stuff inside the tank, and I won't have to have separate pump and regulator outside the tank.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on Feb 12, 2019, 07:41:23
But, it's so BIG.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 16, 2019, 04:28:10
Yeah, it is big. I'm hoping that it will just kind of disappear behind the engine and side covers. Maybe I will paint it black for camouflage. I will post some pictures soon of how it looks with the swingarm in, it is nestled in the space normally taken up by the monoshock.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 16, 2019, 19:50:59
First assembly of the rear wheel and shocks. I started painting the frame, just some spray can stuff that will give a protective coat during the build. After MOT and road trials, the whole bike will come apart to be bead blasted, painted, etc.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 16, 2019, 19:52:56
Further mock up including rear inner fender, rear fender, seat, side covers, grab rail, and fuel pump.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 16, 2019, 19:55:18
Shows the fuel pump nestled where it lives.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Feb 16, 2019, 20:00:08
looking great.I like the location for the fuel pump, certainly much easier than trying to fit one in the tank  :)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on Feb 16, 2019, 21:05:31
Nice.  It really does hide away well.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Kanticoy on Feb 16, 2019, 22:32:43
Just caught up on this. Nice work man, I love it!


Sent from my iPhone using DO THE TON
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: pidjones on Feb 18, 2019, 08:04:45
Love that you're using a seat with enough foam to ride more than twenty miles comfortably. Oh, and the rest looks great, too!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: JustinLonghorn on Feb 18, 2019, 10:38:37
With the side covers, the pump absolutely disappears. Very nice work, man.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Feb 18, 2019, 11:53:50
Cheers, guys! I decided from the beginning that I wanted the bike to feel as much like a factory bike as possible. To that effect I have ensured the following;

-Seat with full padding (no 'brat' style)
-Comfortable footpegs (not knurled tubes)
-Centrestand
-Full size indicators and brake light (in the stock locations)
-License plate holder and reflector
-Full set of handlebar controls
-Fully functional dash, with odometer, etc.
-Socially acceptable exhaust (I will do the best I can, the 690 is pretty loud)

Seat, fenders, and indicators are the biggest deal for me. I like custom bikes and I applaud those that have taken the time to bring them to life, but personally I would not be able to ride a bike that looked cool but was uncomfortable and unsafe. I think maybe it could be a new category of custom bikes, the 'factory' look. I was thinking of printing my own owners manual to keep under the seat.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Maritime on Feb 18, 2019, 13:09:02
Looks great, the pump will not be noticed at all once the engine goes in.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Rat_ranger on Feb 18, 2019, 18:30:15
That's the best way to go on the pump if you can hide it.  There are ATVs that use the same style set up, which is nice for the availability.  I went the intank route on my XS, and can say that while yes it is possible, even in a pretty small tank, it is a pain to get right.  I ended up machining a custom piece to mount a sportster pump and ninja650 FPR inside the tank, and while I'm happy with it the ease of those self contained units would make me reconsider design choices if I did it again.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 01, 2019, 16:01:40
Massive delay caused by the machinist I mentioned earlier that made the swingarm shock mounts. I had the stem quoted on Draft A, then requoted on Draft B. I ordered Draft B, and they made and sent Draft A. Not useable, the dimensions are wrong for the final application. To their credit, they made a replacement in 1 week. But then it has been stuck in shipping for 20 days, and I can't get in contact with the courier. Now that I really have time to think about it, I should have made the stem by myself on the Colchester, and now I may actually have to. Would be fun, and save me 200 EUR. But now I'm stuck in the middle where the stem may arrive any day, so I don't want yet to order the stock, tap, drill and cutter inserts required to make it myself. I will wait a while longer. Next milestone is pressing in the stem, shortening the forks, and making it a roller.
I found a maple seed sprouting in a crack in the driveway, so I replanted it in an ashtray as a little shop buddy. I will update regularly on its progress.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: captainunsociable on Mar 07, 2019, 02:24:04
Really enjoying this project, keep up the good work. This will be something special when it is done.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 08, 2019, 19:23:06
The replacement stem arrived, after 20 days with the shipper. I brought it to my guy and had it pressed into the lower yoke, along with the spacer, bearing, and seal.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 08, 2019, 19:26:18
Forks ready to be shortened. I assembled the forks with no springs, and then assembled the bike for the first time with the forks and swingarm. I set the rake to 26 degrees, and measured the forks to determine how much had to be removed from the springs. I made some top-out spring spacers out of acetal on the lathe earlier, and cut them to length to the new measurements. No pictures of any of this, unfortunately.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 08, 2019, 19:29:36
Assembled steering stem. Pretty happy with this. I'll make the steering stops once the bike is on the ground with the tank on, so I can turn the bars and determine tank / fork clearance.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 08, 2019, 19:34:39
Threw some paint on the frame just to cover up the bare spots. The whole bike will be disassembled after road trials and MOT for a final clean up and beautification, including frame bead blast and paint, tank and side cover paint, and new tires etc.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 08, 2019, 19:39:13
This is the assembly to determine the rake. Just after this the forks were removed, shortened, and rebuilt with new seals and oil. Again, no pictures of this, but it was pretty straight forward work.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 08, 2019, 19:42:00
Roller! This is most complete mock-up to date. Very, very pleased with how it looks.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Mar 08, 2019, 21:15:59
Looking great. Any ideas what you will do for a radiator? I am building a DZR special and I will use a rad from a CR250, china special with extra thick core. For me this offers a good size, most other rads are too wide. Front wheel clearance is an issue I struggled with. Really enjoying your pics
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: pidjones on Mar 09, 2019, 09:42:14
What are you doing for a front fender? Besides keeping rain and rocks out of your face, you will need one to protect whatever radiator you use.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Aussie Steve on Mar 09, 2019, 10:39:55
Top class. Looking cool

Sent from my SM-A530F using Tapatalk

Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: trek97 on Mar 09, 2019, 14:14:14
Looking right at home in there.   8)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 09, 2019, 18:14:35
Thank you, guys! The radiator will be the stock KTM radiator. I've modified it a little to remove some tabs and bits, and the fan will be mounted in the centre, between the frame tubes. It looks fine, and at least I'll have good confidence that it won't overheat. The front fender will be a chromed steel fender, almost full cb550 length. Not short. I've yet to work out the fender stays, but I do have some ideas. I'll probably make steel loops that attach to the fork legs.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 09, 2019, 18:19:22
Here it is outside. I threw the front brake on so I could get it down the ramp, and wheeled it outside. The garage is small enough that I was struggling to see it from the side, so this really let me take some pictures, sit on it, wheel it around, try out the centrestand, etc.
Sitting on it was a huge milestone, as you can imagine.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 09, 2019, 18:22:33
I should start by saying that I don't like this, but it may go forward anyway. I would much prefer a reverse cone muffler, or maybe something like the Mivv x-cone. But, the next milestone on the project is to make it a runner, and using the exhaust that came with the bike will allow me to spend my time and money on things that further that goal, and I can go back and change it later.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 09, 2019, 18:25:54
Shop buddy might actually make it. The cotyledon leaves are kind of dried up and may not fully open, but it is growing new leaves in the centre bit. It lives in an ashtray and I water it by taking a shop rag and soaking up rainwater that seeps under the garage door, and wringing it out into the soil. God help it.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Maritime on Mar 10, 2019, 13:12:45
Ha. Bike looks great, hope shop buddy pulls through LOL.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: doc_rot on Mar 11, 2019, 05:07:03
looks great. My only conern about the muffler would be its very wide and low and may cause cornering clearance problems. Is there anyway to angle it up more?
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Mar 11, 2019, 12:11:56
Looking great. Love the way you got the header to exit inside the frame. 
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: JustinLonghorn on Mar 11, 2019, 12:57:51
I wholeheartedly love everything that is happening here.... except for that can. Ha.

Keep it up, sir!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: JadusMotorcycleParts on Mar 11, 2019, 14:29:11
Shaping up really nicely man!  I am torn with the muffler.  One thing for sure will be an issue is ground clearance, as doc already mentioned, but if it swept up slightly this would eliminate than.  Then the other thing is the style.  You are blending (very well might I add) old with new, so it just depends how much of each you want to through in the mix.  This can looks unmistakably modern - suits the engine and front end well.  However the frame, seat and tank lone themselves more to the classic style and a reverse mega would look best here...  Perhaps one of those nice SS ones from Purpose Build Moto or Cone Engineering or even an M4 reverse mega  8)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Mar 12, 2019, 06:24:45
I agree with everyone's comments about the muffler. I only intended to use the stock muffler to get the bike to the next stage, which is a runner. I see it going like this,

To that end, I want to use the exhaust just to get to the Runner stage, and replace it before road trials. I was thinking like the below.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Maritime on Mar 12, 2019, 08:35:26
Those are the money.  Suit much better once it's running.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: DuckStew on Mar 21, 2019, 11:09:16
Just read the whole thread.  Personally, I wasn't quite into it until the photo where you roll it outside for the first time. 

 ;D It's brilliant.  ;D  I'm floored with how well you've mated the old with the new. 

I'll be keeping an eye on this for certain.  Great work so far!  8)
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 21, 2019, 17:47:35
So it's been over 30 days since I posted last, but I have been working. A lot of the stuff I have been doing hasn't resulted in good post material, so I saved up some. This weekend I completed the radiator mounting, which is a big step on the way to making it run.
Below is the top radiator mount, assembled but unwelded. I think there are some pictures of this from earlier in the thread when I first made it.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 21, 2019, 17:53:31
Here the mount is welded together, and then welded to the frame. In the second pic it looks crooked, but it's within 0.15 degree of the frame reference.
May as well discuss some problems I'm having with welding. Sometimes I weld and it comes out okay, just looks like it was welded by someone who needs more control and practice, fair enough. And then sometimes I'll be in a weld and it will start to sputter, and then the weld will become kind of foamy, with air bubbles and pockets. When this happens, no amount of going over it will fix it. In fact, usually what I will do it grind it out, clean the electrode, start a new filler rod, sand the weld area, clean with brake clean, and clean the ground, and reweld. Usually it will still foam up! Once it starts I can't stop it. But same conditions, like the radiator top mount, the right side went great, the left side sucked. It took a lot of work to correct. I am open to suggestions.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 21, 2019, 17:55:40
Radiator mounted.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 21, 2019, 17:59:59
Rolled it outside for some better pictures. Here the radiator hoses are in place. I got some straight 25mm ID hose for the bottom, and a 90 degree bend for the top.
Seeing the pictures like this make me feel like the swingarm should be shorter.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 21, 2019, 18:10:35
Here is other side in the sun, showing the radiator hoses. Also some other bits that I didn't post about, like the chain, injector, throttle cables, etc. The chain guards (front and rear) are just propped on for the moment, as indication.
The centre stand was interfering with the chain so that got modified, will show that later.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 21, 2019, 18:13:08
Next; finish up and fill with coolant, mount the temporary exhaust, fill with oil, install clutch slave and master, buy a remote fuel tank, install the harness, and try to make it run!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Apr 21, 2019, 18:30:43
The position of the rear guard may be what makes the swing arm appear long. What is the wheelbase now?
Bike does look awesome regardless of the swing arm length though.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Apr 22, 2019, 03:03:59
Hi Pete,
Cheers for you kind words! I haven't measured the wheelbase with a tape measure, but the program I made to calculate the rake and trail puts it at 1501mm, which is around 96mm longer than a CB550. The swingarm is about 160mm longer than the CB550, but the swingarm pivot is moved forward in the frame. Also the seat was calculated to be 15mm higher than a CB550, and indeed I can just get both my feet flat on the pavement.
Agreed, if it weren't for the rear guard it wouldn't look abnormal at all, really. I bought that rear fender on Amazon for like 18 quid, it is garbage. I think it is a Chinese copy of a GN125 fender, or CG125 something like that. I was thinking about polished aluminium, but I want to keep the grab rail, which is chrome, so thought they would match better. Maybe I should modify it shorter and rotate it up some.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Apr 22, 2019, 03:55:34
That length equates to just over 59", which is a very long wheelbase, normal is 54-55". If it was me I would probably shorten the swing arm, but that might be a difficult option. Modifying the rear guard would be an easier option, if you modify it so it fits the wheel curve that would look much better.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Jimbonaut on Apr 30, 2019, 10:41:33
I was about to say the same thing as Pete12 - could be that the radius of the rear fender is throwing of the visual line a little.  Also, if the rear dropped a few inches that may make a visual difference too (are those shocks height adjustable)?

It's really remarkable what you're doing here, kudos man on an incredible bike and the vision to make it happen.  Really inspiring.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 04, 2019, 17:42:33
I do think that changing the fender angle helps, see below. Also I have sourced a Lucas style tail lamp that seems to work ok with that flatter angle. I did find a turn signal that I like, but unfortunately it is so cheaply made that I don't think it is useable. But I do like the shape and size. You can also see that I've sourced a battery as well, getting ready for actually testing the harness.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 04, 2019, 17:47:35
I got the cheapest kitchen cabinets from Wickes and put them up today. 210 all in. They are garbage, but will be perfect for garage duty. I didn't bother too much about getting all the doors aligned etc.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 04, 2019, 18:08:24
Shop buddy is dying. I took it inside so my wife can nurse it back to health.
I will do more work on the bike in the coming weeks, but this weekend probably not. I did order a stainless steel front fender that I will show when it arrives.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: doc_rot on May 07, 2019, 03:15:13
I do think that changing the fender angle helps, see below. Also I have sourced a Lucas style tail lamp that seems to work ok with that flatter angle. I did find a turn signal that I like, but unfortunately it is so cheaply made that I don't think it is useable. But I do like the shape and size. You can also see that I've sourced a battery as well, getting ready for actually testing the harness.

those look very simular to the turn signals I have on my Kawasaki's, except the ones I have are well constructed. I have used them on many bikes.
 about halfway down the page.
http://www.airtech-streamlining.com/miscpages/lights.htm
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: 1fasgsxr on May 07, 2019, 13:33:25
Your shop friend needs a bigger pot.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Jimbonaut on May 07, 2019, 13:51:03
Does shop buddy's pot have drainage? 
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: irk miller on May 07, 2019, 13:54:50
You need a factory service manual.  No sense in determining drainage or the right size of the pot without checking specs in the manual first.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: trek97 on May 08, 2019, 08:56:50
You need a factory service manual.  No sense in determining drainage or the right size of the pot without checking specs in the manual first.

+1. ha
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 08, 2019, 17:13:45
Front fender arrived today. I will NOT place the fender that high off the tire, I just stuck some foam under there to take a picture before being called in for dinner. I was just trying to see how the radius matched. I'll have a think about how to mount the fender, it will be a challenge. You can see from the second picture that there are only 3 holes on the lower fork leg where a mount can be placed, and they are all kind of close together.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 18, 2019, 17:27:44
Inside of the fuel pump, in case you're interested. I had to determine which of the terminals was positive so I didn't hook up the pump to run backwards.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 18, 2019, 17:42:40
Big day! The bike runs. I put the wiring harness in temporarily, hooked the fuel pump up to a remote reservoir, installed all accessories and sub-harnesses, and made it run. I just wanted a baseline before I start cutting the wiring harness. The harness is not too bad, only a few things need to be relocated. One of the computers can live under the tank, that is good. The fuse box must be relocated about 40cm, the starter relay 45cm, and a few odds and ends need to be moved as well. Those are the big ones, though. I will start that soon.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 18, 2019, 17:43:56
Don't you worry about the muffler, I swear it's only temporary.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Luugo86 on May 18, 2019, 21:11:20
 This is a cool project man, I'm in.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on May 19, 2019, 13:20:47
Got into the wire harness today. Just did some planning and cutting in preparation for the relocating. I found a few more things to relocate, like the ambient air pressure sensor, blinker relay, and diode. These are currently located in the headlight shell, but I will have a lot less space than the stock configuration due to using a 7" round headlight. So I will relocate them under the seat. I will use Spec 44, tin plated copper wire to do any replacement or repairs. It's the good stuff. I will also solder in two different resistors, in place of the Secondary Air System solenoid and the fuel evap solenoid. I've read about these on 690 forums. Interestingly, my bike had both systems removed, but the plugs were just left empty, no resistors or dongles or anything, and the FI light was not on. Maybe it had been remapped? When the bike is remapped you can just delete the part of the program that uses those systems, maybe that is what has happened. I will install the resistors anyway. This bike also has a gear position sensor for N, 2, and 3. When in 2nd and 3rd gear, evidently for noise reduction, the map takes (supposedly) 20% power away. My bike had this system disabled. I will enable it. If for some reason I feel like I need more power in 2nd or 3rd, maybe I will do a back-to-back test with the old seat-of-the-pants dynamometer.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 03, 2019, 17:06:39
The harness work is in progress in these pictures. The necessary bits have been relocated, just needs tidying up.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 03, 2019, 17:09:47
All tidied at this point. The harness is now back on the bike and going through testing. It fires up, no FI light, so far so good. Just have to test all the safety systems and switches, horn, lights, etc. Then I will remove the harness again and wrap it. Then I can finish mounting all the electrical bits like the solenoid, computers, sensors etc.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 11, 2019, 17:08:06
New exhaust. I went with a company called Lextek. It was pretty cheap, 99, but it looks to be very high quality. It is reassuringly heavy, has good welds, and uses a pretty thick gauge stainless. The baffle is removable, and is a straight shot through. If it is too loud I may weld the baffle to have less of a direct route. I also ordered a link pipe that is of the correct diameter. This may need to be shortened or welded, we'll see.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Maritime on Jun 11, 2019, 19:19:28
I like that pipe. Im biased though I got two on my gl that are similar.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: killerx on Jun 12, 2019, 16:06:06
Pretty welds
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: cbrianroll on Jun 12, 2019, 17:21:59
What is your Ebay name? I may want some bits....
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 13, 2019, 05:22:41
Hi cbrianroll,
My eBay name is jptupper, I will post here when I am ready to start unloading parts on auction. What is it you are after, I can tell you now if I still have it.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: cbrianroll on Jun 13, 2019, 15:28:13
Kinda want it all lol! I have a Duke 390 that's gonna get more offroad freindly hopefully. Not sure if the wheels will swap but I will need spoked wheels maybe the fork. At this point I'm thinking just handguards.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jun 17, 2019, 05:12:17
The harness is complete and all taped up. I used Tesa 19mm fuzzy tape. It looks really good. Admittedly I went a little overboard, as you cannot see hardly any wire insulator colors in the finished harness, but it does look really tidy. The harness is now back on the bike and the fiddly bit begins of securing all the harness tails to the frame and injector, and mounting all the ancillary bits like the starter solenoid, computers, and other sensors. But at least all components now have a credible plan of where and how they will be placed. Still some temporary cables on there for testing purposes, of course.
I had a chance to start the bike up and listen to the new pipe, wow, that is too loud. I will be fitting a db killer of some kind, the straight through design does absolutely nothing. It didn't even sound good, just loud and blatty. I will link to a movie maybe to show the sound difference when I am done.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: SONIC. on Jun 17, 2019, 09:51:21
This is looking so good.
I can't wait to see it all finished up
get to work!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Maritime on Jun 17, 2019, 11:49:29
Nice clean job on the wiring. Hope there are no shorts to have to trace LOL. But from the looks of it you should be good.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: doc_rot on Jun 18, 2019, 02:45:55
nice work!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 08, 2019, 14:58:58
I pulled the bike down off the lift to check the side stand, it works great. I have done a lot of work lately, but it is all small things and I haven't really taken any pictures. I've mounted the computer, starter solenoid, air temp sensor, barometric pressure sensor, and the regulator / rectifier. It is under the engine in the airflow. Also got new brake and clutch lines installed. Lots of little things. Once all the electric bits are mounted I will move on to the tank.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 08, 2019, 15:17:51
Also mounted is the tip sensor, coolant reservoir, fusebox, and blinker relay. The red cable is a temporary ground strap for the battery, it has been replaced already.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Pete12 on Jul 09, 2019, 08:22:42
Back guard looks perfect now, great job on that.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 10, 2019, 05:29:47
Thanks, Pete. To be honest the bolts are just nipped up so it's still kind of loose, every time I move the bike I grab the fender and move it into a new position. I think it will end up just like this, though. I would like to reduce the angle of the muffler slightly, so that it won't foul the passengers heels. Just bring it down a 5 or so.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: Popeye SXM on Jul 10, 2019, 21:46:44
I'm with Pete, that rear end is looking great as if it was all made that way. I also think a small drop in the muffler would improve looks and practicality. Impressive work, i'm looking forward to seeing it with tank and seat
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: doc_rot on Jul 11, 2019, 11:26:47
when you first proposed this idea i was a bit skeptical but i have to say you are doing a great job, and its looking fantastic. cant wait to see it finished!
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: canyoncarver on Jul 11, 2019, 11:32:39
Very cool!.   What tip sensor did you use?  I'm looking for one.  Thanks.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 12, 2019, 03:36:06
Hi Canyoncarver,
The entire wiring harness including all the switches, sensors, the display, relays, etc. come from the donor KTM 690 SM. That way I knew that it would essentially drop in. The tip sensor could have been deleted by putting some resistors inline, but I wanted to retain all of the modern safety features from the KTM, including the sidestand switch and tip sensor. I DID do away with the 'secondary air system' however. That was too bulky.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 12, 2019, 03:44:59
Hi doc_Rot,
Thank you! Were you skeptical about how it would look, how it would function, or whether it could be completed? I'm only curious, as I had of course had my doubts about all three! I had the idea to put a big liquid cooled single in a classic style frame over 10 years ago, and had a lot of time to think about it. 10 years of thinking about a project, I had a perfect vision of what it would look like. This is not it! I have had to make compromises, and I accept that, in order to make this happen. If I had unlimited money I would have had a custom frame made, used 18" wheels, custom swingarm, right side up forks, aluminium fenders, and classic round gauges. But, this has morphed into something different that I hadn't expected, and that is more of a blending of modern parts and aesthetic. I think that if I had actually enacted my original vision I would have ended up with something that was less bold and interesting. I am really closing in on finishing this, just a few more months I would expect.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: doc_rot on Jul 12, 2019, 11:28:30
i was mostly skeptical how the single would look in the frame
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 15, 2019, 03:37:56
Some odd and ends. Mounted the horn, below the radiator. There was a convenient mount on the front of the engine, so I used that. The bracket will be painted black for subtlety.
The sidestand that I bought had spring mounts on the front and back, so I ground off the front ones. Removed the factory flashing while I was at it. The spring is not the right length, so I scoured the internet trying to find the spring I needed. In the end, I made a small plate to take up the distance. This works fine. In the last picture you can see the plate. You can also see a washer that I made to fit the side stand, on the inside of the clevis. Again, I don't know what bike the sidestand is from, seller said it was a cb550, but I am not so sure. More of a blessing than a curse, however, because I could make a pretty tight washer out of hardened steel and now it fits very, very closely, no slop at all. I do not like sidestands that have play in them.
Title: Re: Project CB690 (KTM 690 engine in a CB550f frame)
Post by: goodoltup on Jul 15, 2019, 03:45:10
Taillight is on, mocked up. Note that the original indicator mounts have been removed. The new indicators will be located below and to the left of the rear grabrail mount, as shown in the first picture.
Made a bracket to hold the relays, and mounted them. Also mounted the coil.
Lastly, I had a go at the front fender mount. I borrowed a 3in1 metal sheer, bender, and roller, and used the roll function to form a 6mm rod of mild steel to the radius of the fender. Came out pretty good.