Cleaning my bike off I noticed this. I haven’t hit anything while riding and I’m pretty good about maintenance. As far as I can tell, nothing in my drivetrain is misaligned and I don’t shift under stress. The chain is broken in 3 places, though. Chain is the shimano XT CN-M8100 12 speed. I use muc off drivetrain cleaner on it and muc-off dry lube. The r/mtb sub had some good inputs but then my post got removed. I bought the chain from Jenson, so I’m pretty confident it’s not a fake shimano chain…
by Solid_Science4514
13 Comments
I would contact Jenson as this looks to be a manufacturing defect. My hope would be they send you a new one or give you store credit to get a new one.
I’m sure you know this already but do not ride that chain! Even at slow speeds a chain snapping can really hurt.
You’re a beast and push 2000w casually!
Never seen anything like that.
My face – :O
I had a quite new sram GX chain do this to me at one point. I moved up a level to xo and xx1 and haven’t had a problem since.
you can call the warranty and they will send you some quick link if you are lucky enough.
I knew Muc-Off was the worst lube you can use but I never knew it was that bad!
Jenson is really good. I would share with them and see what they recommend, as that is def a flawed chain.
I would say it’s likely a fake chain. Jenson gets their product from wherever is the cheapest.
1. It’s a counterfeit chain (I’ve bought them from Amazon and eBay used them and had this exact issue).
2. You’ve soaked in cleaning agent too long (I didn’t realise some can make the steel brittle and cause breakage).
3. You’re putting down serious power and in the wrong gears. My friend bought and ebike kit was wrecking cassette, chainrings and chains as the power put down was too much.
4. You might have a faulty product but I’ve yet to experience this with a genuine Shimano chain.
I can only talk from personal experience so other contributors might have other causes.
Counterfeit? It looks very similar to the real thing, you’d need to compare side by side with the original to notice.
Probably a fake one. So many counterfeit Shimano out there.
Probably a counterfeit, look at the inside plates and see if they’re extended, good way to tell a real chain from a fake.