jamesgregory

found out my actually problem now, snapped the race crank in half! thanks anyway for the comment

after i replaced the woodruff key with the one i made it seemed to work perfect, when the bike broke down just before it cut out, i heard like a grinding noise coming from the engine but the woodruff key was still fine at this stage, however i've noticed that when i spin the flywheel with my hand theirs not alot of compression at all, and if i take the reeds out, the flywheel spins freely for about 180 degrees without spinning the actually main crank bit, is it possible i could have broken the crank? sorry i'm pretty new to geared 50's

hi, was just wondering if anybody could help me out, i recently sold my yamaha aerox to buy a tzr 50, the guy who i bought it off said it wasn't sparking and suggested the magneto, i got it home, and took the flywheel off to find out of luck that the wire had come off the magneto, 10 mintues later the wire had been soldiered on and as the starter motor isn't working, to my surprize bump started first time, however when i took it out on the road, after 10 minutes it cut out due to shredding up the woodruff key as i hadn't tighted the flywheel up, so i replaced it with one i made and it worked and ran, but a few hours later, the bike cut out again and sounded as if something was grinding, i took the flywheel off and replaced the woodruff key, but no luck, it sounds as if it's misfiring and back firing, i have changed the sparkplug and inspected the polini 80cc barrel and piston and all seem to be in good condition, the bike is sparking, and fuels their but just wont start, could anybody please help me out? could i have put the flywheel on wrong? thanks