The craziness continues

The gx50 has 2nm of torque, and 2 hp. At least it should anyway. Whizzers were about 4-5 hp.

Not sure on torque because you cant really work backwards like you can with electric. With electric, just multiply by 5252 then divide by rpm, and you'll have your torque figure.
Threw a chain on my first ride this morning and found that someone on my pit crew forgot to tighten the rear axle. Once that was corrected, the bike started spitting a bit on hard acceleration. That trial run had been over for an hour when Wifey Dear started complaining about gas fumes seeping into her kitchen from the garage. Turns out the carb was leaking from the overflow which tells me either the float is set too high or there's debris in the needle valve. Will check first thing tomorrow which gives me a good excuse for another ride.
More upgrades in my quest to make a silk purse out of this sow's ear. Reverted back to #41 chain on the primary drive because my belt drive was slipping under heavy acceleration. While everything was disassembled I changed the Shimano 22 tooth rear sprocket to a 35 tooth moped sprocket. The new sprocket is too wide for the stock mountain bike Z chain, so I changed over to a stainless steel KMZ 415 chain from my parts bin. The larger rear sprocket resulted in lower gearing and a much better response on takeoff. I like this gearing much better, the bike feels like a real motorbike even though the rake is off. The only fix is a custom steel tube frame with the proper rake and configuration. Might look for a good solid drop loop frame to replace my aluminum one at our village-wide garage sale this weekend. Can you imagine transferring everything from my current build to a new frame? Sounds kind of exciting, actually and it would be an opportunity to sharpen my welding skills ( and my patience).


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Did not score a steel frame yesterday, but have a lead on a pricey vintage bike that I might be able to negotiate down at a local junk shop. It's been hand painted and there's no head badge, so I don't have a clue what it is. It does have a built-in tank horn and an unusual springer fork. She's definitely a junker with tons of rust and bad tires, but I'm only interested in the frame. Will check it out again this week and if I pick it up I'll start stretching to convert everything over.
What do you get when a vintage Schwinn tandem falls in your lap? You get a strong brazed steel frame that can be welded with ease. You get a stretched frame configuration with plenty of room for mounting components and a built-in jackshaft from the rear crank mount (this will eliminate one of my three chains.). I was able to use the SBP freewheel for the jackshaft by reversing it so when the engine drives the shaft, the sprocket to the pedal crank remains stationary.

You also get heavy duty steel rims with what look like 10 gauge spokes and a rear drum brake. As the pictures show, I’ve already removed a rear brace and welded in a mounting plate for the engine, then welded in a top bar for the fuel tank. Will incorporate the springer front end, custom seat, and Shimano hub, along with miscellaneous bits and bobs from the Shanghai Scrambler. Photos of the mini-chopper concept and progress so far are attached.


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