Rail (625Wh) New Trek Rail 7 snapping chains, bent e-13 ring, trashed chainguide

[Kiwimike]

Firrst serious ride out with a mate on his new Rail 7 - and what a complete shambles. M7100 (SLX) chain snapped *twice* and derailed *4 times*. Bike is new - like less than 100km new. On the last run (when we gave up) the E13 chainguide snapped off along with the chain breaking - plastic junk.

I'd straightened teeth on the *steel* E13 ring twice too, so they were perfectly-aligned. They still are, after the last failure.

Chain is correct length for full travel, leaving some mech play.

I'm a Bosch-certified mechanic and have about 3000km of pretty harsh Highlands riding (mostly Dunkeld) on my own eMTB (Decathlon Stilus 85Nm CX, SLX chain, SRAM cassette) - and have never snapped a chain despite innumerable Hail Mary faffed shifts under full load with accompanying cracking out the back.

I'm suspecting here, given the chain is a new SLX, correct length and everything else is sorted:

1. the E13 plastic guide is rubbish, and is allowing the chain to move too much, thereby ramping up over the teeth

2. The steel ring itself is too pliant, and when the guide fails to align the chain, the teeth then bend under the load.

Has anyone else experienced this sort of failure? any suggestions that will work - ie different steel ring / metal chainguide? Having paid £5500 for this bike my mate is not a happy Trek customer...especially when I'm cracking on trouble-free with a £2700 Stilus

Found a thread pointing to this E13 bulletin: https://support.ethirteen.com/hc/en-us/sections/4408352455067-Technical-Service-Bulletins-TSB- - so E13 are blaming 'chainline inconsistencies, and suggest a 1mm spacer to shift the ring outboard will fix things - anyone tried this?

 

[monty1991]

mate had the same prob with his new rail 7. ended up with new chainring, derailleur and chain from trek. different brand of chainring fixed it I believe. I'm 1600k on my 22 rail 7 with no problems. strange it affected some new bikes

 

[Kiwimike]

different brand of chainring fixed it I believe.

Thanks - any chance you could find out which brand/model worked please?

 

[maynard]

Sounds like bike setup was poor . Or non existent.

 

[monty1991]

Thanks - any chance you could find out which brand/model worked please?

the shop fitted a sram chainring which I thought was weird. id go with raceface, hope, unite etc

 

[valecek]

hi. i have the same issue with e13 chainring. noisy cracking noise from chain/ chainring. what chainring ddi you reccomendet please?

 

[Steelyglint]

Chainring loose?

 

[Stihldog]

hi. i have the same issue with e13 chainring. noisy cracking noise from chain/ chainring. what chainring ddi you reccomendet please?

I’ve developed the “crackin” noise as I apply torque when starting a ride. Recently installed a new e13 chainring to replace the old e13 chainring. Originally there was a brass O ring and two plastic O rings installed on/behind the OEM chaining. Because of the shape of the new e13 chainring …I removed the brass O ring. Only then was the correct chain alignment achieved with the Shimano XT cassette. I also use the Shimano 8100 chain with the the SRAM AXS derailer. That setup was quiet, smooth and fast …until I installed another e13 chainring and started hearing the cracking noise.

I suspect a break-in period is needed …I hope.

I also removed the plastic chain guide. There was a few issues with this. Rubbed the chain, difficult to reinstall, breaks easily and prevented the cuff of my pants from passing around when sucked into the chain and chainring. (Never again will that happen to me). Chain guide is gone.
Old chainring. Only chain suck was starting but no cracking noise.

Chainring loose?

It does seem like that but the new castle nut specs increases the torque up to 35nm with a new castle nut. But it’s something to watch.