Stephen (aka steford) said:Another mainteneance question I'm afraid. My chain has started slipping a lot on the outer
chainring - I can see that the chain does not fit snuggly to it anymore
IF a new chain skips on it (jumping over the teeth once in gear when power is applied) AND the teeth
look worn then it needs replacing ASAP, no question about it. The chainring itself might be ok if
you mean the chain ever comes off when changing gear or pedalling very gently.
Are you sure it's skipping at the front - sometimes can be hard to tell whether it's front or back?
Worn rear sprockets are more common.
Quoted message said:Last time I replaced this it cost me £135
You what?!!!! :-)
Chainrings are usually easy to replace and don't have to cost much. What cranks have you got?
Make & model?
Quoted message said:and I was thinking of getting a new bike (approx £400) at xmas anyway so it seems a bit daft to go
too mad on the repair. I've never fixed anything like this myself before so what are the options
for me? I'm thinking I can replace the outer chainring only and put on a new chain figuring that
the outer ring on the front has had most wear and that the rears will be evenly worn so they can
last another 6 months.
Depending on how worn chain is, you might have to replace the rear sprockets (cassette or freewheel)
at the back as well if the chain is replaced.
Quoted message said:Another point is that the gears make an awful noise when the chain slips to the centre chainring
on the front - is that a symptom of the same problem or just a setup/alignment problem?
Some noise when front-changing is normal.
Quoted message said:if it's a seperate problem then that on top of adding the new chain and chainring and I'm probably
out of my depth and may as well let someone else do it all.
I'm sure you could sort it out if you take it step by step:
See: sheldonbrown.comchains.htmlOpen ↗ (sprocket & chain wear, etc)
1. Check chainring bolts are tight, chainring is not bent, derailleurs are working well.
2. If chainring really does look shagged (very pointy, or thin spindly or shark-like teeth) or are
sure chain skips on it, replace (it could perhaps be used on a future bike if expense is hard to
justify). A 5mm allen key is the only tool (usually) required.
3. Consider replacing the chain (or definitely replace if replacing chainrings & sprockets)
4. If new chain skips, replace cassette (by bike shop or purchase tools and DIY).
~PB