Curious about your gasser bike. Especially the weed wacker motor. There is a short oval dirt track here where they race midget cars powered by weed wacker and chainsaw motors. They go about 20 to 30 mph like a bike and have functional wings to hold them in the turns.
Well it´ś not one of those gawdawful cheap chain drive kits & has evolved over 2 decades &
dozen DIY builds with mixed success. The kit as well as the motor is no longer available.
I built a number of DIY friction & belt drives. The last belt drive worked well but was heavier than
the G.E.B.E kit I was avoiding laying out the money to buy. Golden Eagle Bike Engines has
since gone under. Of the many bike kits that were out then, the GEBE kit was focused on fuel
efficiency rather than power or speed. The design had flaws & took a bike with certain specs,
The primary pulley was too small & did not have enuff teeth to properly grip the cogged belt.
Slippage quickly wore out both belt and gear. I solved that with a little larger gear, but that meant
having to pedal off to 8 mph so as not to wear the clutch. The larger gear had potential for greater
speed, but my purpose was to match my cadence range to the engine at an efficient low rpm.
The extreme range is possible thru a symbiosis of rider & engine.
My 2 Tanaka Pure Fire 4000s are 4210s from the last production run. When the yen began to fall
against the dollar they became too expensive to manufacture. It´s a 40cc 2 stroke of remarkable
quality that burns cleaner than most if not all 4 strokes, 2.2 hp (1650w). 4 strokes top out around
7,200 rpm & have twice as many parts to wear out, The tanaka can do 11,000 static or with a
performance carb & exhaust, but stock is 9,000 limited & that´s fine. Everything about
the stock is aimed at a durable engine to last for years. I idle & vary speeds on mlne from time to
time when not in use. I just now shut one off that ran for 1/2 hr. I held my hand to the metal case;
It wasn´t even warm, air cooled, but with a fan flywheel. (maybe an hour, I kinda forgot about it.)
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