Well replaced alternator damper and starting clutch. Which wasn't a bad job. Cranked up only to hear a grinding noise every now and then. Took everything back apart only to find the alternator shaft nut has came off. Tightened again to find the same issue again after a few good cranks over. I cant seem to get the nut to stay tight. When im wrenching on it I have bike in gear. How important is this nut and how can I get it tight?

 

Oh I have a 88 alternator in a 90 motor. I cant get alternator cover off so that isnt a option

 

??

 

Sorry not had to do this particular job yet, a few guys have, Shadow and SebastionBear both have experience in this matter.

If you don't get any replies soon try sending them a PM, they may have missed this thread.

 

There is a how to on this which shows exactly how to do this job.
I suspect the shaft from the centre of the alternator hasn't been seated correctly (there's a lip in the shaft and if you don't seat the thing correctly the alternator will pull at an angle and probably cause the grinding you mentioned)
If you haven't found the how to, let us know and I'll put up a link for you. You should not have a problem tightening the nut, except you need a 14mm ratchet spanner or you'll be tightening one flat at a time for ever.

This may help you - it's the "how to" I used.

http://www.stu.co.nz/cbr1000fix/

https://cbrforum.com/forum/how-tos-8...uccess-139015/