Shimano SLX CN-M7100 12-Speed Chain

Generally, there are two schools of thought for chain selection : get a cheap chain and replace it more often, or buy a more expensive one and try to keep it longer. I am in the "I'm getting the one that's on sale or within my leftover budget" camp, which often corresponds to Deore or SLX level chains.

With its nicely sculpted outer plates, the SLX M7100 is made for Shimano's new 12 speed group which now allows shifting under load. I haven't head of any 12 speed chain breaking so far, so they must be pretty strong. My setup this year consisted of an unusual 12 speed CRM75 chainring mated to an 11 speed XT M8000 11-46t cassette. Although a bit noisier than an 11 speed chain on my setup, the SLX M7100 still did its job admirably, especially considering the XT cassette's too-big-in-my-opinion 11 tooth-jump between the 1st and 2nd gear.

The 55mm chainline of Shimano boost cranks isn't of much help for the lower gears as the chain ends up at quite an angle with the front sprocket. I thought that this would be problematic for the low-range sprockets, but even with the pronounced angle, I haven't noticed any weird grinding feelings or dropped chains when backpedaling. The finish on the SLX M7100 chain remained shiny all summer, even after riding a lot of dusty conditions this season. Chain use after 500km was 0,23% so it would probably still be good for another comparable-length period of time, but I like to use a new chain every season so I don't forget to replace it past its life. Plus the bike just feels fresher when starting a new season with a new shiny chain.

I obviously couldn't experience Shimano's much talked-about shifting under load this summer, but this will be resolved next season with a new SLX M7100 chain driving a new SLX 10-51 12 speed cassette. A few XT 10 speed chains have made their way on my bikes in the past, but I honestly haven't seen or felt much difference between XT and SLX chains. I have always found KMC chains to be a bit less durable than Shimano's, and SRAM's to stretch faster, but anyway now with Shimano's 12 speed shifting, going with their own-branded chains is a no brainer. Especially when they can be bought in price-points and trim levels to suit every budget. SLX strikes a very good balance of performance/price ratio and I'd even recommend this chain to people riding XT and XTR drivetrains if they want to save some money for a negligible weight penalty.