i recently removed my ignition cover to look for the source of a rather loud knocking sound in the engine. the flywheel weight (13oz steahly) was loose and came of with little resistance. the nut was apparently left off during the last bottom end rebuild. my question is, what damage could this have caused, if any, and would it have changed the ignition timing. should i just replace the nut and forget about it? i rode the bike about 5 hrs in this condition.