Re: Shortening chain/Tensioner on Cranbrook
Generally speaking, yes you can run without a tensioner...if, you have some other way to tighten the chain. That will require either rear drop outs that give you some adjustment or you'll have to shim the motor at the rear mount (not a good idea) All roller chain will wear and the kit supplied chain is notorious for premature wear that will require some method of taking out the slack. If I recall the Cranbrook is a single speed (no gears) so no derailer to take up the slack in the pedal chain. This complicates the issue because if you tighten the engine drive chain by moving the rear wheel you also tighten the pedal chain. This is where a chain tensioner comes into play. It is used to maintain the drive chain tension and not effect the pedal side. Much has been written here regarding the tensioner. Do a little research and you'll find a lot of advice, opinions and ideas to ponder about the chain tensioner issue. Keep in mind also that the tensioner is just that. It is not intended to adjust for misalignment between the engine and rear wheel sprocket. It helps to guide the chain onto the rear sprocket but not meant to move it from side to side more than about 1/4 to 3/8" Anything misalignment more than that and you need to address it by other means.
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