is my chainring causing my chain to snap?

i keep snapping my chain…is this the problem?

Nice pic!

Not sure about the chain but could well be – why not just file it down smooth?

How old is your chain?

Are you twisting your chain ? By that I mean being in say big ring and the big cog at the back, for example. That stresses it in a sideway manner which weakens it a lot.

Are you fitting new and old stuff together – worn chainrings + new chain wont work. Does the chain slip ?

File the offending bit off the chainring and check for wear. Measure the chain properly for length to see how much its worn out.

how’s the face jocko?

cjb, does the chain go in the same place each time?

I doubt the chainring is the cause.

Sometimes you just get a duff chain. If it’s shimano, using “normal” pins to re-join won’t help.

um…i dont generally run big ring big ring much…i only run 2 rings on the front anyway…always snaps in a similar area….the chain is 2 months old….

the whole drivtrain is the same age too

leggyblonde – Member

how’s the face jocko?

The eye was gone in a few days, but my big toe and knee is still sore. Off to Drumlanrig and Ae this weekend to try and do some more damage……..

Do you keep the chain clean (chain cleaner) or just a quick squirt with WD40. And have you been riding in very muddy conditions.

what chain is it? i used sram 991s for years with no issues until i had two go on me (on different bikes) in short succession, the last one was literally a few rides old.

The last time i snapped a chain was because it was bone dry with no lube on it at all. (It started well lubed, but gopping mud then water made it really clean and then it dried out)
Do you clean and lube your chain regularly?

i try to clean it regulary…its broken when both dry and wet…muddy and clean…but its always well lubricated…

Chains usually snap due to way too much pressure being applied.
ie. wrong gear wrong speed scenario.

yea…thats when they snap but i dont do that often… and when they do it snapps lol

That ring looks pretty heavily worn, the next tooth away has a proper hole worn into the driving face and it looks like the wear is part way up the face of the tooth, which suggests it is riding up possibly? Cant see it snapping a chain though, in my experience chains snap due to seized links/crossing the chainline too much and shifting under load. To snap a chain when not in these conditions would take vast force or a badly assembled chain (or poor chain material, but would be less likely)

If that tooth damage is wide enough to splay the links as they pass over it, it’s quite possible it’ll cause a breakage. Even if it’s not, it can’t be doing any good, take a file to it, you’ve got nothing to lose by trying.

A few Qs:
1) Is it on a full suss bike?
2) Does it happen on the same/similar route?
3) How did you determine your chain length on the double & bash set-up?

That ring looks like it is well past change date whatever you do. I would change it.

i dont have enough cash to change it lol…its on a g-spot so the chain doesnt extend…