flywheel torque

All right,

Bummed out to hear of so many sheared flywheel keys!! But hey, it's supposed to be the weak link in the chain. All the load on the flywheel is supposed to be thru the taper on the flywheel/crank and the key is there primarily to time the ignition. If in fact there is an unnecessarily high load placed on this system, the keyway loses...a good thing! Where the excess force is coming from and why can't the starting system absorb this force is the question. I guarantee if there are this many cases of sheared keys, YAMAHA will figure it out.

my manual has the cut and paste and says 61 lbs.

i'll be checking my nut, soon. :)

I don't have a WR450 on order or anything but you mention the "keyway loses". I hope it's the key and not the keyway that is getting destroyed.

your correct. It's the woodruff key that loses the fight, not the keyway...sorry


I'm unclear on what the proper torque is for the rotor nut. My manual has the cut and paste that says it should be 61 lbs (I peeled one off and the original printing said 50). However, my manual also came with a correction sheet inside the main cover that says 61 lbs is incorrect and that one should tighten the nut to 47 lbs, loosen, and retighten to 47lbs. So I guess 47 lbs is correct??

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now