Hi

My bike began struggling to tick over and then died. Occasionally it would kick up and then worked and failed again quickly.

After much investigation I found the woodruff key aligning the flywheel had snapped along it's length and was allowing the flywheel to slip out of time.

Has anyone seen this before?

I have a flywheel weight on it but it ran fine for weeks before this happened.

Andy

Had this on other bikes caused by poor surface finish on the tapers or flywheel lockout coming loose. Check there is no damage to the tapers and that the woodruff key slot has not spread. If all ok fit a new key, making sure the key is not too high as to cause the flywheel to run eccentricaly, fit flywheel, torque the locknut up correctly with loctite medium strength fluid. With the cover off kick over slowly and check flywheel alignment, then repeat with flywheel cover fitted to make sure there is no binding.

Had the same thing happen a few years ago on a 2005 Rev 3.

 

Happened out the blue, replaced woodruff key and it never happened again.