Originally Posted by mihlbach

If you want to increase your leverage, you should change your gear ratio, not your crank length. Adding or subtracting even 1 tooth from your chainring will have a much larger effect on your overall gearing than changing your cranklength by 5mm. You should choose a cranklength that is suitable for your height and it most comfortable to you. Never change your crank length to compensate for the wrong gear ratio. Change your gear ratio instead.

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