i need a tap for the crank bolt...the threads in mine are a little bugered up eeping me from tightening the crank pulley all the way down....i just notice the pulley was off on the dyno when i shredded a rib and i pulled the bolt and it was all shiny silver and the first 2 threads were a little messed up, so before i really screw it up i wanna rethread it...any help on where to get the tap and what size it is will be greatly appreciated..

Thanks guys