I thought I could figure out repairs myself but clearly I'm a moron.
I replaced the chain and chainring on my fixie last Saturday, and this morning it got scary loose on me. I started to feel what felt like slack in the chain, but when I pulled over to check it out I noticed that all five of the bolts on the chainring were halfway to falling out.
From start to finish, here's everything that I did when removing the worn ring and putting the new one on:
- Remove old chain (do not remove crankset from bottom bracket)
- Starting with an Allen wrench and a screw driver, I started removing the nuts/bolts holding the old chainring in place. Successfully remove three of the five. Glare at rust on threads of nut.
- Fight with the remaining two bolts, which seem to have seized. Add a small amount of WD-40 to seized bolts. Fight some more. Swear. Attempt to use a hammer to tap on screwdriver to loosen bolts. Lament my lack of a third arm. Swear some more.
- Take a break. Look accusingly at old chainring. Pretend to do something else, in order to lull it in to a false sense of security.
- Attack bolts without warning.
- Realize that the only thing I'm doing is stripping the nuts and coming seriously close to accidentally stabbing myself with a screwdriver.
- Admit defeat, go to LBS. Get a proper chainring nut wrench and a replacement set of chainring nuts/screws.
- Cackling with the newly found power of using the proper tool, removing the frozen bolts and the old chainring.
- Small amount of WD-40 on a rag used to clean rust transfer off of crankset, then wiped down with clean rag
- New chainring in place, finger-tighten new bolts
- In star pattern, use Allen wrench and chainring wrench to tighten bolts
- Repeat above for good measure
- One last time, just crank those suckers as tight as possible
- Install new chain
- Ride to/from work, no problems.
- Ride to work, almost die, s#!t bricks.
All told, I rode about 20 miles between installing the new chainring and the extreme loosening that I had this morning. Did I miss some fundamental step in this process, or was this just bad luck? What can I do to keep this from happening in the future?
EDIT: Now with photos!
I only removed one of the bolts because I didn't have the time to take the whole thing apart. If necessary, I can disassemble the entire thing when I have time.
Also, man my bike is dirty.
Outside of chainring
Inside of chainring
Outside after I removed a bolt
Inside after I removed a bolt
The bolt I removed