I stumbled upon a quick and easy performance boost for the 49cc Honda clone engines. The stock air cleaner inlet is very restrictive, and was causing my engine to bog and hesitate at midrange rpms. I resolved this by simply enlarging the inlet with an exacto knife. I only needed to expand the inlet by about 1/8" across before the engine began to idle more smoothly. Now it runs like a champ. The only downside to this is it made the engine a bit louder, if you consider that a problem
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Now, if only I could figure out a way to hush the gearbox whine...
