Agree with Duck on the standard gearing on the 749, 14 & 39. I've been told not to go below a 14 tooth on the front, a 13 tooth sprocket is too small a diameter for the chain. Normal practice seems to be increasing the size of the rear sprocket anywhere from 41 to 43 tooth. Not sure what works best, 41, 42 or 43 ... I'm sure someone will be along soon who has done the mod and can give better advice. |