Fuel Injected 1962 Honda CB77 Superhawk

[MBellRacing]

So I've held off long enough. I need to share my project! In my introduction thread I chronicled my early build states. Powder coated frame, new paint, rebuilt motor and some electronics-- the usual for a nice resto-mod. I had always planned on doing something a bit more "Cafe", maybe something a little different, and the time has finally come.

Of course, to fit in this end of the forum the bike will have some conventional cafe stuff. It'll have custom clip-on bars that look like the tops of the headlight ears. I'm having made a replica CYB seat from a reputable upholsterer working off an original example. The rear controls have been moved back to the rear-most factory holes... you get the idea. I'll post those steps as I get to them.

The slightly different part of this project, and the stage of the build I'm on now, is the fact that it will be fuel injected. I have been working with a company called Ecotrons which is run by a guy named Matt (you can always trust people named Matt....). He helped me assemble a kit that will work excellently for what I need. They don't have many products quite yet, but the brains behind their engine tuning theory are very brilliant. Their ECU and software is very well put together, simple, and powerful. The kit he made for me has everything I need to get this bike running besides a couple things like a trigger wheel and VR sensor. It was all VERY affordable and the customer service is outstanding.

My plan is (and always has been) to make it very hard to tell that the bike is fuel injected. Before the photos, let me explain where things are going. The ECU, ignition coils, sensor clips, and most of the wiring will be under the tank where the stock GIANT ignition coils had been before. The fuel pump will be housed in the tool tray behind the side covers and feed the injectors and fuel pressure regulator via a long black line that hugs the backbone of the frame. The pressure regulator will send excess fuel back to the tank via a fake overflow line in the gas cap from the space between the tank and the steering head. The trigger wheel is mounted on a little standoff to the generator rotor and the VR sensor will have a custom bracket holding it under the stator cover. The cover itself will need a big spacer so it clears the VR sensor (those things are relatively HUGE). The engine temp sensor is conveniently placed on one of the bolts under the stock ignition rotor cap and the wire is the perfect size to fill up the rubber gasket/grommet. I'll be rewiring the whole bike with a custom loom as to cut down on doubled-up wires. I'll be installing a NOS CYB93 stator and a Charley's Place regulator rectifier. These electrical upgrades along with the LED headlight and taillight (seen here: http://www.honda305.com/forums/led-headlight-bulb-t8546.html) I should have plenty of juice to run all the ignition/injector drivers and the fuel pump.

Now with the photos:

Test fitting the throttles...

Tried tightening them down to measure air filter length and broke off a cheap little vacuum nipple...

...So I relocated it on one with a stronger brass fitting and filled the old holes on both throttles...

Trigger wheel randomly placed on rotor to check out VR spacing...

Engine temp sensor in the points cover. Don't mind the old epoxy or the fact that the cable is heavily bent. I checked to make sure it wasn't kinking, it just looks bad under the insulation...

Wouldn't know it was there! Also, don't mind the stuck screw driver bit-- didn't notice till I saw the photo!...

MAP sensor hidden between the engine and frame...

Coils and ECU in their new home. Need to wrap the spark plug wires in some electrical insulation to make sure they don't talk with the ECU's internals...

Fuel pump in the tool tray...

...Once again, you'd really have to be looking to find it. The blue lines will end a bit short of where they are and be on quick disconnect fittings to black lines out to their sources...

Hard to see with the stuck quick disconnect from the old cross tube, but the fuel pressure regulator is tucked up under the side of the tank...

I seem to have measured a bit shallow for my filter length. They fit, but are VERY snug...

And finally (for now), the CYB93 stator to replace my current one...

Now that I have a place to share, I'll post updates regularly. I'm trying to get as much done as possible before the 24H of Daytona, but testing and seat fittings are keeping me from the project. Worse comes to worst I'll just end up finishing it off late in January/early February. I need to done before March though-- more on that later.........

 

[stonenck]

yes!! awesome dude!

 

[loekm]

Hey Mr. Mbellracing,

This is a very nice one! i'll be following this for sure! When i finish my bike the spare engine will get the same "treatment". Mine is a TR1 engine... I'm still planning parts and electronics, so your build will be very interesting. Keep up the pictures.

Best regards,

Loekm

 

[MBellRacing]

A TR1 twin would be awesome! If you're interested in using Ecotrons, let me know. I'll give you some insight to save Matt some time.

 

[MotorbikeBruno]

Wow. Sign me up for this one! haha. Very cool sir.

 

[JustinLonghorn]

yep, I can dig it.

 

[Barkingmadspeedshop]

Jaw has dropped! Very nice work. 8)

 

[dp9]

FINALLY! been waiting for someone to do this! looks great man, you are already knocking it out of the park.

 

[Erskine]

Bloody Brilliant ........ it's the way forward!

However - A WORD OF CAUTION
When it comes to having blind faith in people just because they are called Matt.
I know 3 Matts.
Two of whom are unable to tell their arse from their elbow and would struggle to organise a piss up in a brewery.
The third is a child genius.
Just saying like

 

[MBellRacing]

Thanks for all the support!

Didn't get too much done today. This holiday season is killing me!!! Christmas parties, Chanukah parties, etc. Too much. It's a tangent on the EFI end of things, but I did, however, get time to cut down my replacement headlight ears to the right size and test fit my clip-on mounts I had machined. I have lost my set screws and will need to try and find some new ones. I also need to get a 1.75" hole saw suitable for cutting chrome-plated steel to cut the bar stock. I then need to make a simple wood jig to make sure both bars are cut and welded at the right angle.

The final question is: should I powder coat them the same finish as the frame or should I chrome plate them like the original bars and the lower trim rings on the headlight ears?

Anyway, this is where I leave things for the night, and likely the weekend. Maybe more after the holiday.

 

[loekm]

Hey Mr. Mbellracing,

Some extra info would be very much apreciated. I've been reading the ecotrons website a bit. But they're talking about 800cc "small" engines. I was planning to use megasquirt EFI in combination wit BMW boxer throttlebodies on my TR1 engine. I've not been searching for the correct sensors etc... But if the ecotron ECU is willing to talk to the injectors of the BMW throttlebodies I don't see a problem in using this system in a bigger engine ( TR1 is 981cc). The good thing on this system for as far as I can see is that it is complete... all the sensors work, and that's a very big plus on the megasquirt.

I will keep reading this and gather some extra info on the TR1 engine in terms of needs for a EFI system! We'll see.

Best regards,

Loek

 

[RoseCityCafePunk138]

I'm digging the clip-on mounts above the ears. I am thinking of doing something similiar to my 69 cb350 build. I'll be tuned into to see how your build goes. I'm also looking for your stock headlight/speedo/tach for my build. Looking good!

 

[MBellRacing]

Loekm, Ecotron's website needs more work than their product does, I promise. They can custom tailor their kit to fit any one or two cylinder motor. The sensors are all easy to work with, come pre-wired to work with the ECU, and are small enough to hide anywhere. I assume the injectors will work fine. Their calculations might be off a bit from stock, but I'm sure it's a simple calibration to adjust.

RoseCityCafePunk138, (good lord, man... long name ) I have a source for quite a few Superhawk, Black Bomber, and CB160 tachs if you're willing to clean up less-than-restored versions. Let me know.

Anyway, today was productive, but not really tangibly so. I fixed the headlight to see how it works with the new ears (one was a bit bend and I had to mend it). It looks awesome. I can't wait to get the ears painted and the bars attached and plated. Modestly, I think it'll look pretty badass and something seldom seen. The big work though, was the wiring. I decided to take off all the electrical tape insulation that Ecotrons applies so I could see the color of it's guts. It's not too bad once you reach in and chase some wires, but it will take careful work to make sure I don't mix the wrong white wire and make sure the multiple blues wind up at their proper destinations. I'll be shortening most of the wires to just a couple inches seeing as everything but the battery and the fuel pump are within a foot of the ECU.

I decided to get my hands really dirty and knock off that right side engine cover to install the new CYB93 stator. It actually went much easier than I had thought. The three wire loom from the assembly comes out about 90 degrees differently than the CB77 part, so some rerouting was neccessary, but overall, seamless operation. Once that was done I installed and wired in the new rectifier/regulator from Charley's Place and the charging system is complete! Finally, I placed the ugly little intake air temperature sensor in the back of one of the air filters. I hate it, but I couldn't think of a better place without disturbing any airflow. Hopefully it won't be as noticeable once the tank and covers are on!

Picture time:

 

[MBellRacing]

So I know it's kind of taboo to reply twice in a row, but I finally was able to get busy on the CB77 again. First thing is I got in a new LED bulb for the Dime City taillight I had bought a little while ago for my cut-down rear fender. I was trying out a couple but settled on the 3-emitter one. It is VERY bright and saves a lot of energy. With the upgraded charging system and little modifications like this the bike should have plenty of electrical ability to keep that ECU and fuel pump going.

I got a big step out of the way today with the wiring. I spend a solid four hours or so cutting, soldering, test-fitting, and covering of the ECU wiring harness. I'm pretty happy with it. It's nowhere near perfect, and the later wires were routed smarter than the earlier ones I did, but it is very well hidden under the gas tank. I still need to make a main harness and incorporate the fuel pump wires, the ECU battery power wires, and the VR sensor wires.

Overall, not a bad day. Unfortunately, I'll be gone for about a week. Hopefully I don't lose my momentum when I return!

 

[Rocan]

following! man oh man this is gonna be a good one. Next bike I do is definitely getting a kick at fuel injection now that I got some experience working with em at school. Nice to see such a beautiful bike being made better thanks to modern tech. would be interesting to see a dyno run on carbs and on injection!

 

[MBellRacing]

Haha... I wish I had that foresight before I swapped the carbs out. No going back now!

 

[MBellRacing]

I'm committing the taboo again! I also lied. I had some time today to work on the bike. Not very long, but enough to get the fuel system all sorted with the exception of sending the return fuel line to the gas cap. It all looks pretty good. A little cluttered with the covers off, but like pulling a duvet over a messy bed, the side covers and tank hide my mess well. As I write this, I also realize that I forgot my fuel filter, so add that to the list. 99.8% done with the fuel system I'd say, then!

I also had some time to play with the digital dash I'm using. I love the Koso product line. I use one on my RVF400. The problem is that it is a very modern dash in a very conspicuous place on a very old motorcycle's headlight. I mocked it up using my plan for the mounting plate. The actual part will be painted black, so hopefully the relative lack of contrast will hide it a bit-- at least while it is off.

I briefly spoke to my neighbor Bob Guynes. He's something of a classic Honda guru. He's built a number of race bikes from the 60s and 70s as well as broken many Bonneville records. He is now making some replica race parts for the Superhawk (and other Hondas using the same parts) built from original castings. He said he'll trade me a set of ducted brake backing plates for the price of my old carbs that he's planning on using on some wild project... Not a bad deal! To anybody else that uses the CB77-style brake hubs, these plates are amazing. They're drilled using a jig that is dead on and really adds some functional flare that you rarely see on drum brake bikes. Here's Bob in the 70's with some S90 and Superhawk race bikes. You can see the sort of brake ducting I'm talking about:

Bob also mentioned that the CYB93 stator I purchased from Charley is worth about $400. He said the CB93 (or CYB... even rarer) is extremely hard to come by. He knows of someone that dropped a small fortune on a restored model. So good news there on a great purchase-- just hope I keep it nice!

Anyway, I'm off for real now, though! I'm sitting at San Francisco airport waiting for my New Year redeye to Costa Rica for three days of R&R before my race season officially kicks off again in Daytona. As I said above, hopefully I can keep up this momentum!!!

Pictures of today's mild progress:

This is how I leave it for a week or so... I think I'm going to miss her!...

 

[MBellRacing]

First day back to work on the bike. That said, today was not very productive. My mess-to-accomplishment ratio was definitely pretty poor. Much of my time was spent pulling different parts out of their boxes to test fit, then leaving them wherever they fall. I also spent a lot of time welding up stuff that didn't work to try and mount the VR sensor over the trigger wheel on the stator. The result came from a cooperative effort between my brother and I, and may I say, it doesn't look pretty. I can only hope it works. The worst that can happen is the sensor bracket moving as it heats up and causing the sensor to lose signal or impact the trigger wheel. Either one would cause a pretty fast complete collapse of everything running the motor.

I finally nutted up and cut the ends off some crappy Ebay clubman bars I had to make my clip-ons. It went surprisingly well. I estimated the angle of my RVF400 bars (which I find comfortable) and set them in the drill press vise at the specific angle and cut them with a 1-3/4" hole saw which is the diameter of the middle of the bar boss I had machined previously. I put the old seat and tank on once they were tacked to test them out. I love them.

So that's it for now, maybe more work tomorrow. Picture time...

 

[MBellRacing]

So quite a lot of work done lately...

I decided to get to work on the headlight and dash. The former first: I cut off the back of the headlight case using a Dremel tool then a hole saw in the drill press. I made sure the hole was flat by setting it on the solid bench and measuring the lip to the surface. Went out and found some EXTREMELY expensive copper sheet and cut it down for a heat sink, making sure I left a lot more material than I thought I needed. My electrical engineering dad and I wired up the emitter panel to the Flexbox LED controller and attached them both to the copper sheet, applying zinc-oxide grease to the back of the LEDs themselves. The lens was then epoxied in place and the whole assembly was placed behind and inside the formerly sealed beam headlight.

I tested it out on a benchtop power supply and, let me say, it works quite well. At about 15W it is easily as bright as the old beam in the same place in the pattern, plus it throws a lot of light off to the sides. Here is a comparison video:

http://www.youtube.com/watch?v=PYulBN6itio

As I mention in the video, the camera wasn't picking up the blueish light as well as the old light's yellowish beam. You'll have to take my word for it, the LED is very bright. It was lighting the whole room while the old sealed beam was lighting a 20-or-so-inch spot on the ceiling. I'm impressed. I did some heat testing as well. The heat sink worked perfectly. It was 116 degrees F on the edges of the copper sheet and 136 degrees F right behind the LEDs. This isn't too bad and WELL within the limits of the system. The remarkable thing was how cool the glass was. If you've ever held your hand over the headlight glass after a long ride, you'll know how much it heats up. Mine was a pleasant 78F. For reference, the light was left on for a little over an hour in a 50F room with no air flow.

As mentioned, once I mounted up the headlight (minus some wires... trip to Radio Shack) I moved on to the dash mount. This was pretty simple. A piece of scrap steel. Ground it down to roughly the right size and shape of the old dash hole, made some tabs to grab the old mounting hardware, and painted it. It has a rubber gasket to keep water out. I'm not very good with this sort of stuff-- my patience is terrible. Honestly, it's not very pretty but seems to be pretty functional (much the same can be said about the rider of this bike...). The dash looks very modern on this old bike, but unfortunately, I think I need all the data it shows to properly manage the EFI.

Also since I've last posted, Bob the neighbor gave me some "inside price" (free) goodies that are quite rare. He first threw me an old hydraulic steering damper. These things are worth $250-300 new and not much less working. I guess the deal is that they're very popular now, but were never that cool back in the day. The racers would buy the CYB racing kit with the damper, drop the bike, bend it, and never bother to put it on-- thus Bob's stash. They never worked all that well either. The people that took the time to pull them apart and get the air out had beautifully smooth actions. The ones that took them off the shelf and bolted them on, did not. It's just how it was. I took the bent, ugly thing home, straightened it, cleaned it, and got it working good as "new". The only problem is that the bolt to mount it the bike is slightly more rare than the damper itself. Ready? $75. A 200mm M10 bolt = SEVENTY-FIVE DOLLARS. "This is the price to be cooooool," says Bob.

When he first handed me the damper, I also asked if he had any CYB or CR rear control bits so I could move my sets back. He rooted through some milk crates and found a rare "C" type long shift rod, as well as the reverse-mounted shifter for use with race pegs. Not bad. Now I have equally rare options. Another snag: the CYB rear sets to work with the CR/CYB shifter is so rare that even Bob, who worked on these bikes in the 60's mind you, has only seen them once in his life. Yeah, not going to find those. I can either stick with the CYB shift rod and keep my stock folding sets, or I can do what most of the old racers did to use the reverse shifter and take a set of pillion pegs and weld them up to work as rear sets. I'll try it out and see which one works best!

Finally, I mocked up the grips and controls onto my tack welded bars before sending them off to my good friend at 034 Motorsports who hooked me up with some welding. Yes, I know there are two different grips-- they're both throttle side so I didn't get one stuck! I love the look. After seeing them on the bike I think I will chrome them eventually. For now though, so that I can consolidate an order, I'm keeping everything the raw, unfinished look. I think it kinda looks sexy, anyway! Christian also helped me weld on the O2 sensor bungs in each headpipe which saved me a lot of hassle.

Pictures:

The headlight case post cut, pre leveling...

Copper sheet cut and bent as the heat sink...

Emitter panel and lens...

Mostly-mounted emitter and lens on heat sink...

Everything minus the wires mocked up in the headlight...

My test bench...

...Yeah, it works...

All mounted in the bike. A few wires and it's ready to work!...

Making the ugly dash plate...

The end result, a hideously modern dash on a vintage bike...

The dirty, broken damper...

The clean, functional damper...

"C" type CYB shift rod and CR reverse shifter...

Mocking up the forward controls...

The welded bars...

And the O2-ready headpipes...

That's all for now, more updates soon.

 

[dcmspikes]

there is so much really good stuff going on here. without seeing the back of the LED you got, how do you keep it from shorting out on your copper mount? and how did you mount the copper to the lens?