Drivetrain bound up on me 20Mph

[MrChimpo]

Today I put the cleaned carb, decarbonized (now no-leaks) exhaust, AX-24 Goodyear V-Belt, and 10-40w oil in transmission final-reduction case. It runs and rides like a new machine, topping out at 32Mph so far, with WAY different power characteristics. The AX-24 is amazing, less slip more power transfer better top end by far. I can hold onto my power band longer and ride with less throttle amongst traffic safely.

Regarding the issue that bound my drivetrain, it turned out to be the final reduction transmission case. I have yet to open it up (need to find a Harbor Freight equiv for the clutch removal tool) to see how much damage was done, but the oil inside of it is filled with metal shavings. Even with the oil in that case it still makes a whirring sound, metalish and cross to my ears =(. I hope that there isn't too much damage done, however, since it was run for a few hundred miles with NO OIL in the transmission I can't expect it to be pretty. Assuming since it rides like normal at the moment, what would be associated with a minor rebuild of the transmission case internals? [Bearings?]