Q: Revs breaking up at mid range and running very rich
Hi, so I have Honda clone 70cc Fourstroke motorbike that I built as a school project, the issues I am having include the revs breaking up at about half throttle and about half way through the rev range, I also am having a big problem with it running very rich resulting in fouled spark plugs, I have however had the carb apart and have the taper needle jet set to as lean as it can be but still having these two issues, ocassionally the bike will stall and sometimes will blow out faint black/grey smoke, and runs much better when its cold. Was wondering if you could tell me if these two are link and possible resolutions to the problems cheers
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