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Author Topic: 1983 XV500 Cafe Racer  (Read 31428 times)

Offline notlob

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Re: 1983 XV500 Cafe Racer
« Reply #15 on: Jan 01, 2013, 15:04:51 »
Putting it on the main stand and saying it needs lowering to suit the forks only ensures that both wheels would be on the floor when on the main stand, not ideal anyhow, kinda defeats the object of having a stand. you need to do it with the bike on its wheels only.
“Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles. It makes me take another look.” >> Steve McQueen

Look at it! God, your project is ... it's everywhere. Your garage looks like you've been committing war crimes against a robot.


Build Threads
1980 Cb750: http://www.dotheton.com/forum/index.php?topic=43860.0
1982 CB900: http://www.dotheton.com/forum/index.php?topic=46733.0

Offline Karlloss

  • Posts: 185
Re: 1983 XV500 Cafe Racer
« Reply #16 on: Jan 01, 2013, 17:07:55 »
I wasn't going to keep the centre stand only need a side stand

Offline notlob

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Re: 1983 XV500 Cafe Racer
« Reply #17 on: Jan 01, 2013, 17:47:25 »
Sorry I didn't really explain myself.
By showing your intentions of making a frame as shown here


It will not keep the original geometry of the frame it will make it worse (relative term) or more relaxed than it was, the center stand is taking the weight off the rear shock so its not sitting correctly and thus unnaturally elevating the headstock. To replicate  the original height of the headstock and geometry you need to let it rest on both its original wheels with the original forks in place. You can then measure the height of the headstock from the ground and the trail if need  be. To replicate this on a new frame.

I dont think I'm  taking a leap in the dark here but the original geometry of this frame could do with sharpening up to get quicker steering more suitable for a cafe racer than a cruiser.

By lowering the headstock, in your case allowing it to sit naturally on the gsxr forks steerer stem , this will achieve the desired improvement is sharpening up the steering.

I dont think you need any frame modifications in that area.

I'm sure someone will come along thats actually fitted different forks to an XV without major frame modification to offer their advise.
« Last Edit: Jan 01, 2013, 17:50:58 by notlob »
“Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles. It makes me take another look.” >> Steve McQueen

Look at it! God, your project is ... it's everywhere. Your garage looks like you've been committing war crimes against a robot.


Build Threads
1980 Cb750: http://www.dotheton.com/forum/index.php?topic=43860.0
1982 CB900: http://www.dotheton.com/forum/index.php?topic=46733.0

Offline Karlloss

  • Posts: 185
Re: 1983 XV500 Cafe Racer
« Reply #18 on: Jan 02, 2013, 16:27:39 »
Yep I hear what you are saying and agree about having the engine in and off the centre stand, the basic drawings are only to get an idea of frame options. Before I stripped the bike I measured the XV forks and headstock height and compared these to the GSXR1000 and SpeedTriple I have and the XV forks are much longer and the headstock higher, I have no idea why Yamaha did this on the XV500 as the other XV models have a lower headstock, I have looked at the XV535 frame which has the same engine size etc. and the headstock is lower on the 535. 

My I will take your advice and remount the engine and measure the headstock height and yes the standard steering on the XV is very lazy, I intend to reduce the rake to sharpen the steering.

Offline notlob

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Re: 1983 XV500 Cafe Racer
« Reply #19 on: Jan 02, 2013, 21:13:36 »
Most of the forks on older bikes are a good bit longer than more modern ones. But quite a bit longer on the cruiser types of bikes. However looking at the photo I guess that the headstock would be a couple of inches lower when on its wheels and therefore would only have to drop a couple of inches onto those forks. Which may end up being ideal.

If the 535 is lower it maybe better to source one of those frames or go the whole new frame like this build
http://www.dotheton.com/forum/index.php?topic=32065.0
although its an xv1000 or TR1
“Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles. It makes me take another look.” >> Steve McQueen

Look at it! God, your project is ... it's everywhere. Your garage looks like you've been committing war crimes against a robot.


Build Threads
1980 Cb750: http://www.dotheton.com/forum/index.php?topic=43860.0
1982 CB900: http://www.dotheton.com/forum/index.php?topic=46733.0

Offline rundown

  • Posts: 260
Re: 1983 XV500 Cafe Racer
« Reply #20 on: Jan 02, 2013, 23:40:55 »
It looks lilke the frame is going to be a major problem.  I believe you might be able to cut the whole front of the frame off and lower and rake the steering head more vertical.  that said, this seems pretty complicated to do without a jig and some pretty sophisticated measuring tools.  Perhaps you can source another frame?

Offline biker_reject

  • Posts: 2146
Re: 1983 XV500 Cafe Racer
« Reply #21 on: Jan 03, 2013, 17:16:34 »
I think I'd have a go at trying out the gixxer fork and tree set up before chopping up the headstock, of course, I chopped on my frame.  Just on the opposite end.  Ha!  Check my thread.  See what you think. 

Offline Karlloss

  • Posts: 185
Re: 1983 XV500 Cafe Racer
« Reply #22 on: Jan 03, 2013, 17:18:36 »
Notlob, cheers for the link, that build is not too disimillar to one of my solutions, thanks for pointing me in the right direction.

Offline Karlloss

  • Posts: 185
Re: 1983 XV500 Cafe Racer
« Reply #23 on: Jan 05, 2013, 13:33:43 »
Ok, so I have remouted the engine and tried both the orginal forks and the GSXR forks for comparison before I do any cutting and chopping. As you can see from the pictures running the GSXR front end without frame modifications would reduce the ground clearance too much, although the rake angle has improved, i.e. reduced to sharpen the steering.

Offline full on tin

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Re: 1983 XV500 Cafe Racer
« Reply #24 on: Jan 05, 2013, 16:24:38 »
Love xv builds. Exciting to watch if you do try and tackle the geometry change. but, when you mocked it up with the suspension loaded it looked pretty mean and lunging forward.

-What tank are you running? will it cover up most of the area you plan to tweak?
-Do the GSXR bearings match up to your headset? or do they require mods?
-Any plans for the rear wheel? This is the one area of these bikes i dislike. I've seen some conversions, but they seen like a big task with the differential. Friend of mine found a chain drive XV, lucky guy. 

Cheers, keep it up!

Offline cbSteve

  • Posts: 33
Re: 1983 XV500 Cafe Racer
« Reply #25 on: Jan 05, 2013, 18:14:27 »
Just looking at the pictures, I think it looks perfect with the GSXR forks. I know nothing of geometry, trail and suspension, so don't mind me. Yes , I see that you loose some ground clearance and that is maybe not good. Maybe a little in this case will be ok. Maybe you can make up a little in the back with a taller rear tire? I don't know but with the right seat and tank it could look very good!  This post is of little use but I really dig the pic of the modes so far. Good luck. Thanks for sharing and I will continue to watching!

PS sometimes if you keep the modes simple  you have a better chance of finishing and getting to ride the bike (ask me how I know ;))
« Last Edit: Jan 05, 2013, 18:26:19 by cbSteve »

Offline biker_reject

  • Posts: 2146
Re: 1983 XV500 Cafe Racer
« Reply #26 on: Jan 05, 2013, 23:39:50 »
The thing is, we aren't exactly going to be dragging knees with these things, are we?  Of course, you'll be using a 17" gixxer wheel.  I opted for 18"'ers on both ends.

Offline Karlloss

  • Posts: 185
Re: 1983 XV500 Cafe Racer
« Reply #27 on: Jan 06, 2013, 05:44:56 »
[quote author=

-What tank are you running? will it cover up most of the area you plan to tweak?
-Do the GSXR bearings match up to your headset? or do they require mods?
-Any plans for the rear wheel? This is the one area of these bikes i dislike. I've seen some conversions, but they seen like a big task with the differential. Friend of mine found a chain drive XV, lucky guy. 

Cheers, keep it up!
[/quote]

I haven't decided on a tank yet, the standard tank is awful and uses the return flow vacuum fuel tap/pet cock with a fuel pump, so I'm going to bin that and use a tank from something else. The issue is that the XV frame is wide as the airbox is part of the frame above the carbs, I was thinking of constructing a twin spar frame to allow conical air filters to be mounted on the downdraft carbs, as I like the look of the V-twin engine without a side draft carb obscuring the view, however as the standard carbs have a pressure restricted float cut off as standard the bike uses a fuel pump, I have decided the best option is to go with a single side draft carb, this should also allow me to use a single tube backbone frame.

The GSXR bearings don't match the XV headstock as the GSXR uses tappered roller bearings and the XV uses ball bearing races, however the steering shaft is the same diameter top and bottom and the same length and has the same threads, in fact the XV shaft looks more substantial, would you believe. As it looks like I'm going for a complete new frame I'll get a headstock machined up, it can't be that expensive.

I had plan with the rear wheel, of at least I thought I did, I was thinking of using another GSXR front wheel, this would give me the advantage of being able to use a disc rather than drum, my thoughts were that the width of the hub of a GSXR front hub would be narrow enough to mount the spline drive for the XV and still keep the wheel centred, however it's a no go, so I'm looking at using a spoked hub from an XV 535 and changing the rim to either a 17" or 18" as the 535 uses a 15" rim, more expense but I'll leave the wheels to last, as I'm trying to do this on a budget.

Offline Karlloss

  • Posts: 185
Re: 1983 XV500 Cafe Racer
« Reply #28 on: Jan 06, 2013, 05:53:07 »
I agree it does look good with the forward stance on the GSXR front end, although this is just with static sag and no other compontents on the bike, no fluids and no rider, and as much as I'd like to think I'm lean and slender, I'm far from it at 210 pounds, so I'll aim for a bit more ground clearance.

Offline notlob

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Re: 1983 XV500 Cafe Racer
« Reply #29 on: Jan 06, 2013, 12:38:44 »
You do have a headache there Karloss.
Ground clearance doesn't look great and with the addition of evrything else and a rider its only getting worse. If your not dead set on USD forks try the early 2000 zx9r c and e model RWU forks they are longer than recent USD forks and fully adjustable. I Have a set ready to go on a cb900 so can let you have the measurements.
I'm presuming the rear wheel is 18" and the front 18" or 19" so keeping the original front wheel and making it fit the gsxr forks would give you some more clearance but maybe not enough. But would give you matching wheels and negate the further headache of reengineering a back wheel.
Maybe a frame redesign is the better option but no less complicated.
I think which ever way you go is not going to be easy and straight forward.

Good luck
“Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles. It makes me take another look.” >> Steve McQueen

Look at it! God, your project is ... it's everywhere. Your garage looks like you've been committing war crimes against a robot.


Build Threads
1980 Cb750: http://www.dotheton.com/forum/index.php?topic=43860.0
1982 CB900: http://www.dotheton.com/forum/index.php?topic=46733.0