Wife's bike had a flat so I repaired it but while replacing the rear wheel I noticed a bushing type pat in the way of the drop out. I pushed it back in so it slid quite easily. But I took the wheel off to see what it was as I haven't seen this on our other bikes with Shimano hubs.

I take the wheel of and slide the bushing off. I can slide the cogs off along with a portion of the rear axle inside. I think that's what it was so I slide everything back together then try to screw the bushing in thinking maybe it had threads but nothing. The outer section of the bushing has knurls but no flat spot for a wrench or similar on the sides. Heck I don't know, is it supposed to screw into the axle cause it didin't?

When the bike was new I took it bak to the shop at the free tuneup. I mentioned to the mechanic that I thought there was a bit of play in the hub. He said it was teh Bontrager way. They used replaceable cartridges in the hub for easy replaement. If it had more bring it back but it never did. I asked another mechanic at another store, he said the same thing and I know he's the honest guy.

I replaced everythig and tried it out, everything seems normal. So is this the way these wheels are? Maybe just part of the replaceable cartridge system. I never noticed this before. Nothing would secrew back in, just slid right together and works fine!

Are they made this way?

Almost sounds like the cassette locking ring?

Not the c/lockring, much smaller inside the diameter of the lockring. Only about the size of a dime in diameter and 1/4 long. Hmm!

The hub should not have more than a very small amount of play