The Raptor 660 motors are kind of known to wear the crank tapers , so it's not unheard of with these big bore Yamaha's . May be more a case of not enough torque on the nut and the flywheel flexes slightly at higher rpms that wear the tapers. If the flywheel "locks" on the crank end fairly easy and requires to be pulled off the taper should be ok .
.
__________________
'86 XT600/3TB motor,,, '88 XT600, ,,'92 XT600e,,, '08 Husky TE510,,, '05 DRZ463,,, '95 KLX650 ,,,'96 KLX650
|