Chain/Cassette wear

joey54321
joey54321 Posts: 1,297
edited August 2013 in Workshop
My park tools chain stretch tool is saying measuring at 1 which it says means I need to replace the chain and that the cassette will be toast by now as well. However, by inspection the cassette seems fine. Only slightly shark finning on one of the gears and the rest still seem pretty good. Should I just replace the chain or the cassette too?

Comments

  • farrina
    farrina Posts: 360
    edited August 2013
    There is no problem just replacing the chain for now. if there is an issue with the cassette it will become rapidly apparent when the chain starts to slip, most likely on your favourite sprockets, at which point you have your answer.

    Regards

    Alan
    Regards
    Alan
  • doug5_10
    doug5_10 Posts: 465
    +1
    Its very hard to see cassette wear just by eye, get your new chain and try it out. Tenner it skips like a schoolgirl! :wink:
    Edinburgh Revolution Curve
    http://app.strava.com/athletes/1920048
  • keef66
    keef66 Posts: 13,123
    At 1% chain wear and If you can actually see wear on the cassette then I'd say it is almost certainly toast. Save yourself the frustration and possibly bruised testicles and order a new chain and cassette.

    And measure the chain more frequently, replace at 0.75% wear, and you'll get at least 3 chains to your new cassette.
  • joey54321
    joey54321 Posts: 1,297
    Thanks for all the advice, have just ordered a 105 cassette and ultegra chain.

    One question though, if I replace the chain at 0.75 everytime how do I know when the cassette is worn?
  • doug5_10
    doug5_10 Posts: 465
    joey54321 wrote:
    One question though, if I replace the chain at 0.75 everytime how do I know when the cassette is worn?

    It will sound like a bag of spanners, probable poor shifting and skip/slip like said schoolgirl.
    Edinburgh Revolution Curve
    http://app.strava.com/athletes/1920048
  • keef66
    keef66 Posts: 13,123
    As above, when you get to the point where a new chain skips on it.

    I'm up to 5 chains on this 105 cassette. Probably replacing them a bit early; total mileage is 5000. Next change will be chain and cassette.
  • bikeit65
    bikeit65 Posts: 995
    Don't mean to hijack your post, but what chains do you guys use eg Shimano, KMC ??
    https://www.instagram.com/seanmcgrathphotography/
    Trek Domane SL7 GEN4
    Planet X RT58
    Cannondale CAAD 10 2012.
    Pain.. Is weakness leaving the body.

    HATING LIFE-CYCLES FROM 2011
  • dodgy
    dodgy Posts: 2,890
    Also, if chain has worn to 1%, cassette will have worn appreciably so that any new chain even if it doesn't skip badly, will still cause the new chain to wear quickly to 'mesh' with the state of the existing worn cogs.

    Always measure with a steel ruler and change at 0.75% wear. You should get 3 chains per cassette if you do.
  • bikeit65
    bikeit65 Posts: 995
    dodgy do you not trust the chain measuring tools?
    https://www.instagram.com/seanmcgrathphotography/
    Trek Domane SL7 GEN4
    Planet X RT58
    Cannondale CAAD 10 2012.
    Pain.. Is weakness leaving the body.

    HATING LIFE-CYCLES FROM 2011
  • dodgy
    dodgy Posts: 2,890
    Bikeit65 wrote:
    dodgy do you not trust the chain measuring tools?

    Great question, and source of much debate. But yes I do to a point, but the majority of chain wear tools measure roller slop or wear. Not the overall length of a portion of chain. The only 'drop in' guage that measures properly is the Shimano TL-CN41

    What I do is use a 'drop in' gauge then when it starts showing 0.75% use a steel rule.

    See here for more detail.
    http://pardo.net/bike/pic/fail-004/000.html
  • joey54321
    joey54321 Posts: 1,297
    Got my new chain and cassette today and they are so loud! Ultegra 10 speed chain with 105 10 speed cassette with a sram force mech. Will it get quieter from riding? wear in a bit?
  • smoggysteve
    smoggysteve Posts: 2,909
    I have always managed to get a lot more miles out of a cassette than a chain. Unless it is really worn to the point the teeth look like shark fins the chain will work with it fine. You don't mention how many miles the chainset has actually done. A cheaper chain could wear prematurely and mean the cassette is servicable.
  • keef66
    keef66 Posts: 13,123
    joey54321 wrote:
    Got my new chain and cassette today and they are so loud! Ultegra 10 speed chain with 105 10 speed cassette with a sram force mech. Will it get quieter from riding? wear in a bit?

    Is Ultegra 10 speed one of the directional chains, and if so, have you fitted it the right way round?

    New stuff often sounds a lot louder than the stuff you've just replaced because it's worn together.
  • joey54321
    joey54321 Posts: 1,297
    It is a directional chain and the markings on the chain are on facing out on the driveside (as per the instructions, although some of them are upside down).

    So will the new chain and cassette quieten down a bit once they wear together?

    I don't think its the chainrings as
    1) they look pretty good with no shark fins
    2) happens on both rings and the inner ring has barely been used.
  • keef66
    keef66 Posts: 13,123
    Did the cassette come with a thin spacer and if so have you fitted it? Also, is the indexing of your gears spot on?

    I imagine it will be a lot quieter after a few hundred miles wear and a bit of light lubrication.
  • joey54321
    joey54321 Posts: 1,297
    Hey, it came with the spacer at it is on. The index is correct (although I did have a play with the it but only made it worse, I think the sound an out of index rear mech makes its very noticeable. The current sound is a different kind of noise).

    I'll ride it anyway and see what happens. Thanks for the help guys.
  • keef66 wrote:
    Did the cassette come with a thin spacer and if so have you fitted it? Also, is the indexing of your gears spot on?

    I imagine it will be a lot quieter after a few hundred miles wear and a bit of light lubrication.

    Apologies for highjacking:

    keef66 - I recently bought a 7 spd cassette, 12 - 28 c/w thin(0.6mm) spacer. 12t sprocket is loose, the rest rivetted together.

    Does the spacer go between cassette block and bottom of freehub; between block and 12t sprocket or between 12t and lockring?

    At 0.6mil thick, what is it spacing?
  • keef66
    keef66 Posts: 13,123
    I've only used a thin spacer with a 10 speed Shimano cassette on an 8/9/10 speed Shimano freehub.

    No idea about spacers for 7 speed cassettes. I don't imagine it's meant to go between the 12t sprocket and the rest.
    Would help to know what make of cassette, whether it's Shimano / SRAM or Campag spacing, and what wheel / freehub it's going on.