Snapped chain link, is the chain now junk?

lissard

Last Saturday down on the Rebel Tour I managed to snap my chain. I was trying to jump on the back of a passing group, stamped down on the pedals and bang, chain gone. Nearly went over the bars, I count myself lucky as I didn't come off and when I veered over towards the other side of the road there was no oncoming traffic.

A few really helpful guys from one of the clubs down in Cork helped me fix my chain. We took out the broken link and popped in a 10 speed quick link so I was able to limp home. I assume this chain is now junk. It's the first chain that has ever broken on me (11 speed Shimano 105), I only have the bike 6 months with just 2.5k on the clock. I keep the chain clean and lubed and I am somewhat surprised that it would break so soon - only checked the length a few weeks ago and it was perfect. On my older bike I had an 8 speed KMC chain and even when badly worn, it never snapped. Are these 11 speed chains a lot more fragile?

Other thing that happened to the drive train was part of my rear mech seized up a few weeks ago, the spring was not fully engaging so my chain was under-tensioned and sagging. CSS replaced this derailleur under warranty. Could the chain snapping be a by product of this? I guess replacing a deraileur would require the chain to be broken prior to refitting.

Wishbone Ash

I'd change it anyway as there's 2.5k on it for the sake of peace of mind if nothing else.

11 speed chains are narrower than chains of old so I presume they are weaker.

Cee-Jay-Cee

I snapped a 10spd KMC chain last year and repaired it with a link from the section I removed when first fitting it. It's been 100% ever since. It had less than 500km when it happened.

In your case I'd just buy a new chain for peace of mind.

at1withmyself

Its not normal for a chain to break when so new and can sometimes but an indication of another issue. Your issue with the derailleur sounds like there might be still something wrong with the drivetrain.

As others have said get a new one but have someone review the drivetrain and make sure everything is aligned ok. If the bike had a fall something might be knocked out of place.

Also keep an eye on crossing the chain as its not good for the drivetrain

http://www.bicyclechainrings.com/crosschaining.html

This is not good practice on most systems.

lissard wrote: »

Last Saturday down on the Rebel Tour I managed to snap my chain. I was trying to jump on the back of a passing group, stamped down on the pedals and bang, chain gone. Nearly went over the bars, I count myself lucky as I didn't come off and when I veered over towards the other side of the road there was no oncoming traffic.

A few really helpful guys from one of the clubs down in Cork helped me fix my chain. We took out the broken link and popped in a 10 speed quick link so I was able to limp home. I assume this chain now junk. It's the first chain that has ever broken on me (11 speed Shimano 105), I only have the bike 6 months with just 2.5k on the clock. I keep the chain clean and lubed and I am somewhat surprised that it would break so soon - only checked the length a few weeks ago and it was perfect. On my older bike I had an 8 speed KMC chain and even when badly worn, it never snapped. Are these 11 speed chains a lot more fragile?


Other thing that happened to the drive train was part of my rear mech seized up a few weeks ago, the spring was not fully engaging so my chain was under-tensioned and sagging. CSS replaced this derailleur under warranty. Could the chain snapping be a by product of this? I guess replacing a deraileur would require the chain to be broken prior to refitting.

ford2600

Where did it break?

At quick link or link pin? Or did a side plate fail?

The inner dimension of 10 & 11 speed has not changed but the side plates have got narrower, meaning the narrower 11 speed side plate needs to be made from a stronger material than the 10 speed for same relative strength. Higher strength usual means less ductile.

Peening and less ductile is not a good combination!

We should all just go back to 8 speed...

Wishbone Ash

ford2600 wrote: »

....Peening and less ductile....

Busy Googling now!

lissard

The link pin broke away from the plate. It was a regular chain link and it looked to me like metal fatigue where the link pin joined the plate.

tomasrojo

If it's an old chain, maybe get a new one. As said, you can fix it with another bit of the original chain, if you installed the chain yourself and cut to length with a chain tool, but with an old chain (many thousands of km), it seems likely that the chain is worn.

lissard

Thanks for the advice folks - much appreciated.