Originally Posted by Jim Bud
I have a question, and I know nothing about bearing, most everything else of course, but not bearings.... :)
My questions is; does the need to tighten the rear pivot bearings ( which I suspect that many bikes do not have done until it's been running loose for a while) have a negative effect on the rear drive bearings?
In other words, if the rear pivot is run loose for a sustained time, will it screw up the final drive bearings??
I am no GS expert, but if that rear pivot is what you are refering to, that would not have anything to do with the pinion in the final drive. That adjustable pivot pin allows the driveshaft housing, and final drive housing to articulate, and yet have the pivot bearing clearance taken up, (similiar to a swing arm pivot)
The pinion (small bevel gear) probably has a nut pulling it tight in the housing, the large bevel gear is held in place by both bearing outer races being sandwiched between the final drive housing halves.
As for gear contact pattern shimming, they must be shimming on the pinion end, because looking at the pic's posted above, there does not appear to be any adjustment lateraly on the large gear.
Todays modern engineering/machining can allow for parts to all fit nearly the same, as opposed to yester year where each assy was an individule and required individual shimming. Or the lack of adjustable shimming may actually be the problem.
But I still do not see how that design keeps axial load off that left side bearing, especially with wear.
They make ball bearings that can take axial load, and radial load (angular contact bearing is one example), but I have never seen one in a final drive.