• The year is important, because up until 1974 these parts were different.

• I have never done this work, but going by the diagrams it looks like you can slide the felt seal out without disturbing this collar. If the collar does need to come off, then I suspect you can use two (2) equally spaced pry bars to extract it from the shaft.

You can access the hub's internal parts from the other side. Be aware that the wheel bearing races are an interference fit and the hub must be heated to pull the bearing race(s), and heated when re-installed. When you open up the other side of the hub and extract the bearing race, you can pull out the spacers and have a look inside the hub. Maybe you can access the felt at that point. The stack of spacers must go back in exactly the same way they come out. With respect to pulling the cap on the drive cog side of the hub, I've never tried that. I would assume an interference fit there as well.

@wobbly Thanks for your input.

@8053 Thank you for your input. I did not see any access to the felt seal from the inside of the hub when the bearing stack was removed for servicing. I put the hub back together so I will have a look at prying the collar off if I get brave enough to try.

I got to wondering about this, so I dis-assembled an extra rear wheel I had hanging from a rafter in my garage. No worries on this wheel since the drive cup/cog is long gone on this one. Here's what I found. On my wheel, on the drive spline side, I took a screwdriver and extracted the top hat spacer and then popped the seal out. On this wheel there was no felt per se, just a regular old rubber wheel seal. The top hat spacer is just a surface for the lip of the seal to run on. The top hat "brim" is inboard of the rubber sealing lip. On the hub that I just opened up, on the drive spline side, the wheel bearing is captured between the bearing race and the open end where the seal and top hat reside. I might try to heat the hub and pop the inner obstruction off the spline side of the hub. The only other way to get that bearing out that I can figure would be to heat the hub and drive the bearing and race out the other way. That just doesn't make any sense to me. When I last serviced a rear wheel bearing set, I pretty much took the wheel apart to where this one is now and cleaned and greased the bearing in place. 

@8053 Thanks for sharing this info. I know from research there were a few different hub configurations which evolved through those years and luckily there is info out there to sort it out. I won't pry on anything until I find out for sure how that felt seal comes out on this 71 model.

I think the best thing to do is get the correct new seal first then figure out how it goes in by looking at its profile.

I enlisted the assistance of fellow airhead member with much more experience than me to service a rear wheel for my R75/5. Many thanks to Dave Fahringer. Anyway, the hub must be heated up to what we call "spit hot". This is where a drop of spit sizzles on the aluminum. Then we used the axle as a drift and drove the whole bearing stack out of the other side of the hub. My earlier speculation about this topic is/was WRONG.