i cant remember if the threads are meant to be lubricated or fitted dry but if it doesnt specify lubing the threads, i'd recommend spraying the end of the crankshaft (where the bolt goes into) with brake cleaner, then blast it dry with shop air and then install the bolt. Sometimes the threads are dirty or unneccessary oil gets pushed into the end as the bolt is driven in. The pressure has to go somewhere.
Anything that rotates should be balanced. The crank is internally balanced but if you slap a heavy pulley on the end which isnt balanced then it's going to upset things
|