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Chain/Cassette replacement

reaction57reaction57 Posts: 20
edited January 2019 in MTB workshop & tech
My 12 speed chain has reached the 0.5 wear limit and I am about to replace it.

Is it false economy to replace just the chain and not cassette + chain ring at the same time ?

Both the cassette and chain ring look OK, they are Sram Eagle XO1 so to avoid spending another £300+ I will leave them for now if that's sensible.


  • slc123slc123 Posts: 407
    I would suggest that if they look ok no need to replace them. Replace them when you need to. No point in wasting money. I’ve replaced lots of chains without doing the cassette or chainring.
    Cannondale Trail 27.5 | 2015
    Titus El Chulo 27.5 | 2017
    Trek Slash 9 27.5 | 2015 (building)
  • steve_sordysteve_sordy Posts: 2,141
    The recommended "limit" is 0.75%, measured as "stretch". So replacing at 0.5% could be said to be too soon. But it is worn chains that do the damage to the gears, so some replace the chain early and get the benefit in longer lasting gears. I never managed to get more than three chains out of a cassette, even though I too changed chains early. That was about 550-600 miles per chain and approx 1700 miles out of a cassette.

    Which 12-speed version is it? The upper end has specially hardened chains. The chain on my Whyte T130 is the SRAM XX1 and it is lasting extremely well. It is on target to last six times longer than any other chain I've ever had. I measure the chain regularly with a vernier caliper so I can see the chain slowly "stretching" as it wears. It has already done more than 1400 miles and it is still only one just over a third worn.

    I would definitely buy another one of those chains.
  • billycoolbillycool Posts: 833
    edited January 2019
    As has been said, it depends on the condition of your cassette and chainring.

    If it was all new, there is no reason why you can't get a couple more chain changes in. There is no exact formula but you shouldn't* need to replace everything for every chain change.

    *edited cos I is stoopid.
    "Ride, crash, replace"
  • I have the mid range Sram Eagle X01 drive train with XG-1295 cassette and Silver X01 chain.

    It has done 2200 miles of mixed condition riding, wet/muddy and dry/dusty over the last year.

    I am fairly meticulous with my chain maintenance.

    I am sure that I read somewhere that 0.5 was the limit for 12 speed chains, so I will fit the new chain on the old cassette/chain ring and see how long the cassette lasts.

    I was nervous about the cost of the Eagle drive train but it's never missed a gear, gives super gear shifts, the 50t gives great climbing ability and I've only had the chain come off once when it was derailed by a twig, I'll definitely stick with it.
  • steve_sordysteve_sordy Posts: 2,141
    Ref Reaction57's last post

    I'm glad it's not just me then! :D
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