Australian Cycling Forums - Bicycles Network Australia

Hi guys

Long and the short of it without boring you with a life/sob story.

Carbon crankset, obviously the teeth are some form of alloy. I noticed one of the teeth(tooth?) is bent.

Causing slippage. Can these things be rectified? Or does it require a matching small chainring replacement?

Cheers

I would suggest that anything you try to do to it will only weaken it.
Do you know how it was damaged?
You could try to straigten it , however, if it fails (breaks) while you are loading up the chain (ie Climbing a hill) it could possibly cause damage to other components on the bike when the chain flys off, under load.
Would be safer to replace the chain ring and the chain also. If the ring is damaged then the chain may also have an issue, but then a worn chain on a new chain ring, will only prematurely wear the new chain ring - so yeah, I'd change both.

rebilda wrote:I would suggest that anything you try to do to it will only weaken it.
Do you know how it was damaged?
You could try to straigten it , however, if it fails (breaks) while you are loading up the chain (ie Climbing a hill) it could possibly cause damage to other components on the bike when the chain flys off, under load.
Would be safer to replace the chain ring and the chain also. If the ring is damaged then the chain may also have an issue, but then a worn chain on a new chain ring, will only prematurely wear the new chain ring - so yeah, I'd change both.

I haven't got a clue.
It has been professionally serviced 2 rides ago. (If that means anything)
First ride, the chain somehow slipped into the frame and got caught.

Seemed ok afterwards.

Then next occasion it felt seized at one stage and then it started skipping like skippy the kangaroo.

Thanks for the suggestions, I'll look into it.

It is worth having a go to straighten it. If you can bend the tooth back to straight again it will be fine, even if the tooth breaks off in the process a missing tooth won't have any effect in practice.

SRAM even marketed cassettes with missing teeth as being some sort of shifting improvement. If a cassette cog can do without a tooth then a chainring certainly can.

DoubleSpeeded wrote: It has been professionally serviced 2 rides ago. (If that means anything)
First ride, the chain somehow slipped into the frame and got caught.

Seemed ok afterwards.

Then next occasion it felt seized at one stage and then it started skipping like skippy the kangaroo.

Thanks for the suggestions, I'll look into it.

It doesn't sound as if the 'service' was really professional unless there is something else that is missing from the description. 'Somehow slipped into the frame' is the bit that needs the clarification, it is not clear whether this is an adjustment issue or some other problem. These things never happen whilst 'just riding along' even though that is how all warranty claims seem to start.

As it is only two rides after a service then it might be worth taking it back. If it is a workmanship issue then they would have some responsibility for the subsequent damage.

Cheers,

Cameron

ironhanglider wrote:It is worth having a go to straighten it. If you can bend the tooth back to straight again it will be fine, even if the tooth breaks off in the process a missing tooth won't have any effect in practice.

SRAM even marketed cassettes with missing teeth as being some sort of shifting improvement. If a cassette cog can do without a tooth then a chainring certainly can.

DoubleSpeeded wrote: It has been professionally serviced 2 rides ago. (If that means anything)
First ride, the chain somehow slipped into the frame and got caught.

Seemed ok afterwards.

Then next occasion it felt seized at one stage and then it started skipping like skippy the kangaroo.

Thanks for the suggestions, I'll look into it.

It doesn't sound as if the 'service' was really professional unless there is something else that is missing from the description. 'Somehow slipped into the frame' is the bit that needs the clarification, it is not clear whether this is an adjustment issue or some other problem. These things never happen whilst 'just riding along' even though that is how all warranty claims seem to start.

As it is only two rides after a service then it might be worth taking it back. If it is a workmanship issue then they would have some responsibility for the subsequent damage.

Cheers,

Cameron

Heya Cam...
yeh its a real bummer man...

not something you would expect form a Shimano Dura Ace Derailleur either... as well a Dura Ace chain...
well i dunno if this would put a piece to the puzzle for you....
apparently at the time of service, the guy reckons there was s slightly bent chain link so it required a quicklink...

after that it all went downhill.

on the small chainring too... ive seen matching large ones but havent seen a small one other than a complete crank-set.