I have an 82 Yamaha Virago, although when I look up the parts on an online catalog, it seems to be an 84.  

Point is, I have the famous starter clutch grinding.  Some people seem to think it can be shimmed and there is a service bulletin m82-0198 that addresses the issue.

However I am unclear on what the shimming will accomplish, and what I need to do.

When starting, the gear slips and grinds a bit.  I would say more slipping and spinning than anything.  Sometimes will catch for a split second then just spin.  The inside edge of the starter clutch gear is worn badly on the corner making it round.  The starter clutch does NOT spin in both directions, leading me to believe it is still ok.

Also the flywheel seems to have some corner edge wear also.  This doesn't appear to be too bad though.

Where would I even find these shims?  Would they help?  Is there a place to read bulletins with pictures?

If I replace the starter clutch, do I need to replace the inner and outer parts?  Someone was saying there is an updated part.  How do I know if I have the updated one?  

You could try this http://www.tholt.com/virtip.html or http://www.youtube.com/watch?v=qfCLfO7avP0 or http://www.drpiston.com/81_83_Starter_Paper.html

I don't know if the parts are interchangeable with the 920 or not. I had a 87 750 an 85 1000 and a 98 1100 and they all ran great for me. I am now on a 07 Roadstar 1700.  

I had a 82 750 and a 920 and the 920 had this problem. when the gears were engineered they were done wrong and it resulted in the annoying grinding. there are kits out there to replace the inner gears to compensate for the engineering blunder. i installed one of these kits and it worked great.