Spun Rotor

I'm haveing trouble keeping my rotor on.I have sheared the woodriff key on the rotor of my 76 KZ 900(SEE SIG BELOW)3 TIMES NOW.There is some scaring on the end of the crank and inside the rotor.The last time it happened(2weeks ago) I used valve lapping compound to try to improve the fit,then cleaned it with brake cleaner and glued it on with green Locktite 609 and let it dry 24 hours.It failed again today while doing a compression test.Can anyone tell me what the best options are here.Should I just go to a stronger locktite,and heat for removal if nessesary later?Is this a common problem?

sounds like a really high compression motor,slot end of crank for longer woodruff key.

Post edited by: wireman, at: 2006/09/24 22:20

Only getting about 160 psi comp.

thats strange,i used to have that problem on my z1 but it had way too much compression though!:evil: it would shear the little halfmoon key off when trying to crank with electric start,so had end of crank slotted for full size keystock which worked till starter shot craps and wouldnt turn it over:P

the key dosen't keep it on it keeps it in alignment with the crank
on some engines you leave the key out of the flywheel to change the timing
if you leave the key out and press the rotor on the crank and twist it it should want to grab
the taper on the crank and rotor make a interfearance
fit
is there a lock washer ?is it any good ?
lap it again then heat the rotor, 350 or 400 for 20 min or so the put it on hot with the key, tighten before the crank gets hot
best of luck to ya

Thanks I like that idea ef heating it. If it fails again I'll give it a try but since there is scoring in the rotor Im probably going to have to replace it.Had the same problem with a Yamaha Blaster once ,It had a stepped or offset key to adjust the timeing..