hey guys im having a problem with my 2012 wolf 50cc gy6 engine scooter. i took off the cylinder head to swap it out for another because i accidentally stripped the threads in the sparkplug housing, and all attempts to repair it actually made it worse. but i noticed what the problem might be after reading a few threads here. while installing the new head and putting in the cam i actually managed to pull the timing chain forward a few links.. i went over to the flywheel to make sure it was still at TDC and it was so i reassembled it normally but it would not start up. is it possible that i have thrown the timing off?

 

If the TDC mark is lined up and the mark(s) on the cam gear line up when tension is on the chain, the timing is right. If it is "off" you may have bent the valves.