As some of you may remember, my MTB has a shaft drive instead of a chain drive. After some experimenting with different greases, I have stuck with Red Line CV-2 grease spiked with a little Paratec tackifier added (Thanks, bruce381!) for the past 3k (2,9xx) miles. Last Saturday, with BITOG in shambles and looking for a therapeutic activity, I decided to break the shaft drive down for inspection and regreasing. First of all, so you have an idea of how the shaft drive works, look at this picture: Let's start in the rear with the rear transmission gear. I see essentially no wear, the lube still looks good: The above shown rear transmission gear meshes with the rear hub gear, which is connected to the rear wheel axle. This gear also looks fine. I believe it is sufficiently lubricated and I don't see any abnormal wear: On to the front transmission gear, which is the smallest gear and the one which suffers the most wear and tear. As you can see, the grease migrates, due to high rotational speed and centrifugal force, to a large degree off the gear and onto the shaft: Here is the same gear with most of the grease cleaned off. You can see surface imperfections (pinpoint pockets from casting) and maybe some galling? Please comment! I did not take a picture of the crank axle gear, which drives the front transmission gear, because it appeared in very good condition (similar to hub gear). The weak spot in the system appears to be the front transmission gear, mostly because it's such a small gear. All in all I'm happy with it's durability and performance. While I do see wear and tear on the gear contact points, the teeth have not lost any noticeable amount of thickness, the teeth edges are undamaged and the tranny still operates smoothly. Does anybody believe I could choose a more suitable lube for the front tranny and crank gears?