Last Tuesday I did a complete swap of the rear wheel on my Trek SU 100.  It took me a little while to throw this short post together because I’ve been distracted meticulously following the upcoming snow storm.

Sometime before the holidays I noticed my rear brakes were rubbing, and it turned out to be a crack on the side of my rear rim.  I blame Boston’s potholes.  I did a little reading and determined I didn’t want to wait for the wheel to “fail catastrophically” despite the fact the crack seemed innocuous enough.  Many bikers had probably had this happen to them, or done this repair, but this is the first time I’ve encountered a cracked rim.

The offending crack.

When I was back in my apartment after the holidays, I went out to REI and bought a new rear wheel, already set-up with a hub and spokes to save the hassle.  I asked the shop to give me a wheel “just to get the job done” since this is mainly a commuter bike.  I figured I could improvise / borrow some tools, but I ended up needing a Cassette Lockring, and a Chain Whip.  Due to my impatience to finish the repair, this involved a second trip to REI for tools.

Derailleur and gears

Some pre-repair pics.

Pretty grimy cassette

The lockring is the black piece that screws into the hub, holding the cassette on the bike.  After watching some videos on youTube for cassette removal, I learned it is fairly easy to strip the lockring, and it makes a loud clicking noise while loosening/tightening it.  When replacing the lockring, it appears you want it a little more than hand-tight, so that there is no play in the gears (they can’t shift at all).

The right tools for the job, complete with degreaser and grease. I also recommend a big wrench.

Since I was about to disassemble the rear gears, I decided to degrease everything, including the derailleur.  The degreasing was by far the messiest part, and I spent most of the time dealing with the derailleur pieces.

Cassette off the wheel

Tire with tube removed, everything is ready to be put on the new wheel.

The clean gears and cassette on the new wheel.

Fully assembled.

The one issue I had with with the repair was the rim I replaced was double-walled, so the spokes were recessed.  The new wheel is only single walled, so it is weaker, and will probably need some truing down the road.  So far it rides fine, and I don’t really notice a difference.