Necessary to replace these?

[JetDriver]

I've got the rear wheel off and have decided to check the drive shaft and pinion cup.  I look at the manual and now see that the "stopper ring" (is that the pinion seal?) on the pinion end of the shaft should be replaced with a new one.  Is that necessary?  Also,  the damper holder plate bolts are supposed to be replaced with new.  Does everybody do that?

[Daniel Meyer]

I don't replace the "stopper ring" unless it's torn up, and I don't replace the bolts in the wheel either...just add a little anti-seize or loctight (corrosion is the issue in my opinion).

[GOOSE]

#1 on daniel meyer....ifyou replaced everything that the manual says to replace when you service something on the bike, before it was all said and done, then you would have a practically new ride.  reuse those parts unless they appear broken or screwed up.