Okay I give up, I bought this 1990 Yamaha warrior , I have had to put in 2 crank woodruff Keys ,,it just broke the second one, Im ready to roll it out in the back Yard and shoot but I have alot of money in it, anybody got any good ideas on the problem ? it runs great and has a new starter clutch as well. Im open to any suggestions short of giving it away.

 

Take the broken pieces to a local machine shop, and ask them to make you one from a solid piece of HARDER metal.

 

do NOT make a hardened one. Woodruff keys are DESIGNED TO BREAK. Diagnose the problem and fix it. Make sure you key slot on the flywheel isn't worn out too. Are you using cheapo hardware store woodruffs or yamaha ones?

 

somethings binding or moving... take a closer look but dont get a harder key..... let them break if not something else will.....(missing a part ?) spacer ?ect.....

 

def don't get hardened one.I'd be looking into your flywheel and shaft condition...

 

Found the problem, the inside of the flywheel is worn, when it broke the flywheel key before from a bad starter clutch, the inside of the flywheel is probally worn 10 thousands more and it wobbles a small bit, either i will do the new flywheel or the Loctite 660 fix. thanks fellas

 

Your findings are correct. If the flywheel is not seated properly they shear the keys off.
The next probable reason Ive seen keys shear is because the nut securing the flywheel has not been properly torqued to the correct spec.

 

now that Ive thought about it somemore, The second time I did the key, I dabbed some oil on the crakshaft then installed the flywheel, Thus causing this to happen, If you take the time and think about it you can always figure out what the heck you did, I cleaned up the flywheel and crank with sand paper and lapping compound followed up by a dremel wire brush, then i measured it and its not that bad, Im going to install it totally dry and see what happens tommorrow.