After initially mocking up a Honda first-gen, air-cooled ATC250R engine into this frame, I had a chance to think freely about what I wanted to pursue in the workshop. I have decided, at least for now, to concentrate on “cheap and cheerful” — the stuff I can truly have fun with.
I really enjoyed the twist-and-go nature of The Bride. With my right wrist permanently FUBAR, trying to modulate a traditional twist throttle becomes prohibitively painful within just a few miles of riding. Therefore, plan to stick with clutchless bikes: either semi-auto Honda Cub style, or CVT torque converter. I have picked up a couple different twist and trigger throttle options that can mount on the left handlebar.
I yanked the incomplete hunk of Honda motor out and sloppily shoved a brand new, complete 250cc 173F diesel engine into the engine bay. That was enough to verify that this combination could work. Everything fits, with enough room behind the engine to run a jackshaft across the frame. Hot dog!
I don’t plan on running a CVT, just a centrifugal clutch. With plenty of diesel torque down low, a comparatively heavy chassis, and only 5 horsepower on tap, I think greater drivetrain efficiency when running WFO wins out over the more spritely acceleration variable gearing provides.
Sourcing sprockets for the drivetrain is surprisingly challenging. Going with #35 size chain seems to provide the most universal options by far, even though Size 35 chain has a reputation of being a bit wimpy. Fortunately, stronger, higher quality name brand chains are out there.
There’s a lot of fabrication ahead, but it all appears to be pretty cheap and rudimental stuff, in both concept and execution.
What will the tank and seat be? Will it get lights? Get licensed for the street? Who knows. The beauty of this style of project is that I’m not going to worry about any of that until after it starts and runs.