Thts exactly what happen to me bike was running great then one side exhaust was firing harder then the other changed the cdi,coil,jets,needle position everything then I bought a fly wheel puller and took off the fly wheel and noticed the woodruff key was gone thts what keeps it in sync might wunna check it fly wheel pullers are cheap and so are the fly wheel key always go from cheapest to most expensive learned tht the hard way
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