Project '71 ('73?) CL350... fuel injection and electronic spark control?

Looks like you moved into a much nicer workshop... err, balcony.

Thanks for all the kind words everyone! It is getting a lot closer to completion, but still needs a good bit of wrench time.

Yea, the balcony is nicer at this apt, but its a wood floor as opposed to concrete, so if any fluids spill, they can run down onto the balcony below...:eek1 hasn't happened yet but I need to be careful when working on it out there.

Anywho, a bit of work's been done shortening & laying out wiring harnesses, but the most photogenic stuff has been to the mounts for the throttle bodies & the fuel rails.

The original plan had been to use both the CBR rubber coupling and the CL coupling, but when I actually mocked it up, it seemed... slightly flimsy.



So, instead, I went to work to put together more permanent. Time to get all the rubber off of the CL's couplings to get some flanges I can weld to...



I also had some 1 1/2" tube laying around that I had been using as a breaker bar, and the ID was as perfect of a match for the newly created flange. Unfortunately, the OD did not even remotely match the CBR couplers, so I needed to find something that did. A run out to the hardware store netted a short piece of 1 1/4" pipe (no idea what schedule). After a bit of cutting and welding (wow, I'm a bit rusty with the TIG torch), I got these:





Not pretty at all, and they still need a bit of finishing, but they position the throttle bodies so that the filters will clear the battery box and the megasquirt, but not far enough to hit your legs when riding. I also welded on some tube compression fittings to the end of the rails, so I can use a bit of hard tubing between the throttle bodies for the fuel instead of hose-clamping some rubber line and hoping it holds.

Didn't make much progress on the wiring harness recently. My parents are coming to town for thanksgiving so this weekend my gf and I were thoroughly cleaning the apt & organizing, and I convinced her that the best place to store most of the motorcycle stuff was on the motorcycle itself. Now, she's mostly reassembled, minus the mounting for the MegaSquirt, headlight, the real handle bars I'm going to use, gauges & front turn signals... and of course the wiring to make it all work. I did spin it over with the battery & starter, and there doesn't sound like there's any contact in the alternator. The MegaSquirt will be going right underneath the battery tray in pic 2, between it and the little storage box that the rear fender rides on. Thats a little bit low & close to road grime & water for my liking, but for now it'll be good enough. Pic 3 tries to show how far out the alternator casing sticks out. Not too bad, but I had to bend the shifter out by about an inch so it wouldn't hang up on the mounting bolts for the casing when upshifting







Unfortunately, I opened the gas tank and was greeted by the tank sealant having separated from the inside of the tank along the top (and who knows where else), and massively peeling. Guess i'll just need to strip it out & try again. I had heard good things about the POR15 tank sealant stuff; maybe I just didn't clean it out well enough between steps?



And then this last one is the gas tank latch that I kludged together from some spare metal and welded on there, since the stock one was long gone when we got the bike. Not pretty, but it works in the same way.

What a fantastic project. I've heard of enough people having that kind of failure with POR15 that I don't think I'd ever use it. Did the tank have pinhole leaks or anything? If not, the inside should be clean enough from the POR prep to not need any kind of sealant.

I've never filled the tank all the way up, but from about 3/4's full it didn't leak. However, the rubber seal on the cap was mostly missing when my friends & I bought it, and it was rusty enough to plug the carb within 10-20 min of riding (even when not using the reserve). The cleaner seemed to do a pretty good job though; I don't feel much rust if I hook my fingers around under where that film used to be attached. Maybe before fixing it again I can try to knock out a couple dents in it, and weld on more appropriate fuel fittings that won't be choking the quite oversized fuel pump.

One other question... What would you call the style of handle bar that's on the bike right now? I'd like to get one thats a bit bigger & thicker walled to use so I can drill through it & route the grip wires inside. The one thats on it is from a bicycle and doesn't quite fit, plus seems too thin to try to drill & expect it to stay in one piece in use.

Ditch the POR15. I have a fiberglass tanked and it failed not once, but twice.

I'd used Caswell sealant. Put that in over a year ago for my fiberglass tank and not one single problem since. Much better product from both a chemical and user standpoint. Best $60 I've spent.

http://www.caswellplating.com/aids/epoxygas.htm

I've never had any long-term luck with either the POR-15 stuff or Kreem. Getting all the old rust out is damn near impossible, and if the liner doesn't fail immediately, it fails within a year. What has worked is taking it to a shop that does radiator and fuel tank restoration work and having them boil the rust out of the tank and then do a professional epoxy job. But it trashes the tank paint.

- Mark

Those bars are called by some "superbike" bars, very similar to the RD350LC standard bars. Most bike retailers should get them easy, or Ebay. You can also get them in alloy, both with a 2" rise and pullback, but also flat (no rise) "drag" bars (2" pullback), made by Renthal, you can even get the bar mounts to go with them. A really comfy set would be a set of MX bars, about 4" rise and 2" pullback, but might be higher than you want (although about 2" less rise than stock). The steel bars might be better than alloy, coz the alloy bars are 4mm thick, so have less I.D. for your wiring.

Great project mate! Excellent left-field solutions to getting an "old girl" breathing new life again. As a long-term owner of a CB350, I applaud your application.

Oh yeah.......if I can make one of these run with standard CV's, then 28mm smoothbores, then with a 36mm Alfa Romeo Dellorto, then finally with a single 1.75" SU carb, then I reckon this will be a breeze compared to your 13BT tuning wise.

Have fun man!

INTERESTING!!!

Looking forward to see the end result.

That gas cap latch was recalled because it easily became depressed in a collision, causing massive fuel leakage. Your local Honda dealer should have the replacement key-latch part, for free if you do it right.

I'll need to look into the latch, thanks for letting me know! This one requires pulling up on the tab to get the top to open, and the broken one that had been on there appeared to work the same way, and b/c of the amount of "hook" to the top piece, really requires a good shove to the top of the cap and yank on the tab to get it to open

Taller MX style bars would be good too; I had bought a set of stock bars that was supposed to be off a '72 CL350, but it had some metal sleeve welded on that half-overlapped with the clamps, so I couldn't use it. It also wasn't drilled for the wiring from the left handgrip, (but had an almost identical right grip/throttle/switch assembly to the CL) so maybe this was a piece from an SL or off-road derivative. I don't expect the tuning will be too difficult if it originally made due with a carburetor and inertial ignition advance; to start I could just load up a fake ignition table based off of the stock unit & very basic fueling. The biggest challenge will probably be just the process of datalogging, since I can't sit the computer on the passenger seat and adjust while driving.

That Caswell stuff looks like it might do the trick; I'm going to look into any places locally that could boil the tank too.

The original gas cap release was actually a push mechanism.

This be the new one:

http://store02.prostores.com/servlet/motorcyclesolutionsllc/the-4444/Honda-Gas-Cap-Latch/Detail

I'm not necessarily pushing that store - they just happen to have a good page showing the part, what it fits, and what it replaces.

This is the old one:

If you get the tank cleaned out (be it acid, boiling, electrolysis, whatever) give consideration to a good electroless nickel plating. A good job will see the tank last for 20+ years with no corrosion whatsoever. If you're going to the trouble of cleaning out the inside of the tank there's no reason to coat it with glop unless you're trying to seal leaks.

Been quite a while since I've posted anything from this project, but its been slowly progressing. No pictures right now, but I've been slowly working on various small mounts & whatnot for the relays, fuse box, regulator/rectifier, battery & the MS itself, and have made lots of progress on the wiring. I'm leaving the stock harness pretty-much intact minus ignition, battery, charging & coil wires, with a connector from the CBR harness to pass power to the lighting as well as hook the stop switch on the handlebar. The charging system & fused power is all new (although very roughly based on the stock CBR), and the wiring for the megasquirt itself is all new.

At this point, I just need to finish up adding a couple connectors for the fuel pump & air temp sensor, and running a bunch of ground wires, and the harness should be good to go. Not much in the way of pictures right now, but I'll try to grab some over the weekend.

Still need to decide what to do about the tank, as well as mount the fuel pump, filter, & run the fuel lines. I managed to break the stock fuel pressure regulator too, so I'll need to find another one of them. I also need to get a narrowband O2 sensor or two, & weld the bungs onto the exhaust for them. Still a bit of work, but with some luck, it could hopefully be time to try to start her up in a month or so.

Keep it up! This is going to be so awesome!

Back from the dead, again. Its gotten cold enough to discourage me from doing too much to the car in what little free time I have. Since last post we've moved again, and now there really isn't space in the living room or elsewhere in the apartment for a motorcycle. Therefore, it's living down in the storage unit, surrounded by tools, boxes of parts, and other project-related stuff.


Anyhow, I've been making a bit of progress on the wiring, and tying up loose ends here & there. Basically just the power & ground need to be run for the fuel pump (since I'm still not sure where I'm going to put that), and then the air temperature, O2 sensor, and idle valve need to be wired up. Then, its wrapping the whole mess up in conduit & harness tape.


I'm planning on using one of the solenoid air valves from the emissions control on the project car as the idle valve for the bike, since its pretty small, electrically controlled, and is meant for a vacuum tube. That way, I can just plumb it to a vacuum port on each throttle body after the throttle. The fuel system is going to be primarily made from coated steel hard lines & compression fittings, since I can make those more compact than barbs & rubber hoses, plus they'll be less likely to leak, puncture, pull off, melt etc. I wanted to do an in-tank fuel pump, but the shape of the CL's tank really doesn't leave me anywhere to do it where the pick-up will be relatively close to the bottom, so external it is.


And lastly, when testing all of the electrical systems, all the lights, accessories & whatnot seem to be working as intended now. Plus, when cranking the bike over with the starter, the retrofitted alternator & CBR rectifier/regulator is putting out 8.5V, a very good sign!

Glad this project is still going, keep at it!

+1

This is such a cool project.

Can't recall if I've mentioned this earlier (it's been so long..) but I've been trying to solve the fuel pump issue as well, subject is a CB550-4. I really want to use a Suzuki in-tank pump & have a smashed up GSXR tank was planning on grafting the flange area into the bottom of the 550's tank at some point. Maybe some experimentation with a junk CL tank is in order?
The other trick may be to use a smaller 'surge tank', place the pump in that, somewhere in the 'triangle' area under the seat, and just feed it from the main tank.