Re: Someone explain please the difference b/w a gear reduction box and a shift kit!
2 stroke China motors have built in gear reduction. Speed of the chain sprocket is far less than the engine crankshaft.
Most other motors used on bikes do not have built in gear reduction (Honda, Hueshang, etc). The crankshaft speed must be reduced by a gear box (like 4G) before it can usefully drive the rear wheel.
So if you have a Honda motor mounted in the frame of your bicycle, you must use a gear box and you can also use a shift kit as well.
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