I meticulously look after my drive train, for example changing my chain out before it is too stretched. On my 18 mth old bike with about 6500 km on the clock I noticed today that the teeth on my FSA chainring are very disparate. Some are quite flat and others quite sharp ( nearly knife-like ). Could be I just never noticed this before. Anyway, any comments on this ? Is it the norm ? Is summat amiss ?
Chainring teeth
- Thread starter jimbut
- Start date
Page may contain affiliate links. Please see terms for details.
HLaB
Marie Attoinette Fan
Hard to say without seeing it but some teeth on chainrings are different to aid shifting.
gbb
Legendary Member
- Location
- Peterborough
At 6500km, especially if its a 9 / 10 speed, i'd assume the chainrings want replacing. As HLaB says, some teeth are machined differently to aid shifting, but the pointed teeth do sound like wear.
Fattman
Active Member
- Location
- Roydon, Essex
I would humbly suggest that the chainrings should not be terribly worn at 6500km, especially as you have been careful with your chain length. I've run my chainrings for ~8k miles and they are still fine, and a lot of that has been through the abrasive cr*p that builds up off a long commute...
Found this picture of some FSA chainrings (a quick Gooooogle did it) - here You can see that the teeth at 12 - 2 o'clock appear quite different from those at say 5 - 6 o'clock. Such variability is even more apparent on this Ultegra crankset. This is all part of the ramping systems to try to improve gear changes.
If you can see gaps beneath the chain when it's wrapped round the chainring, though, I believe that is a sure sign that something's mismatched - though it is more likely the chain than the chainring.
Found this picture of some FSA chainrings (a quick Gooooogle did it) - here You can see that the teeth at 12 - 2 o'clock appear quite different from those at say 5 - 6 o'clock. Such variability is even more apparent on this Ultegra crankset. This is all part of the ramping systems to try to improve gear changes.
If you can see gaps beneath the chain when it's wrapped round the chainring, though, I believe that is a sure sign that something's mismatched - though it is more likely the chain than the chainring.
Ta for all the replies. Yes I was in my LBS and had a good squint at rings on the bikes in there. Also studied online pics of FSA rings. There is nought wrong with mine. They are as they should be, some more pointed, some less so, some very flat looking. LBS reckon with looked after chain ( replacing when needed ) I should get a heck of a lot more mileage yet. Anyway one more sorta related question while I`m here. Can I replace the chainring ( when I need to do so down the line ) with any 50T BCD 110 out there? Know it is only aesthetics BUT I love the look of a compact outer called I think "FSA Super Road Compact". Can`t imagine this to be a prob as I have FSA chainrings on but, never having replaced such an item on any previous bikes, not totally sure. PS my crankset is a compact ( in case I failed to mention ).
gbb
Legendary Member
- Location
- Peterborough
Ive replaced my FSA chainrings with Stronglights, no problem fitting them.
You're right, the replacements are not so nice to look at though.
Crankarm
Guru
- Location
- Nr Cambridge
Nothing wrong. The teeth are shaped so to aid shifting. What will happen over time especially if you don't change your bike chain went it is knackered is that the hollows between the teeth will elongate so when you do fit a new chain it will jump. If this happens you WILL need a new chain set. So my message is to buy a chain checker tool such as the Park Tool and check your bike chain regularly for stretch.
