Chain derails on cassette when back-pedaling

ilovedirt
ilovedirt Posts: 5,798
edited May 2013 in MTB workshop & tech
I've got a new 10sp zee setup on my new bike, and I've set it up so that it all shifts correctly, but when I backpedal, the chain derails on the cassette. For example I've got it on the biggest sprocket, and it'll start to derail into the higher gears. Any ideas why? This is really irritating me.
Production Privee Shan

B'Twin Triban 5

Comments

  • Chunkers1980
    Chunkers1980 Posts: 8,035
    Why are you back pedalling?
  • nicklouse
    nicklouse Posts: 50,675
    it it normal and happens on all bikes.

    more so when everything is new.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • ilovedirt
    ilovedirt Posts: 5,798
    Why are you back pedalling?
    Do you never backpedal?
    Production Privee Shan

    B'Twin Triban 5
  • ilovedirt
    ilovedirt Posts: 5,798
    nicklouse wrote:
    it it normal and happens on all bikes.

    more so when everything is new.
    Fair enough, I guess I've never noticed it before. Or perhaps my old drivetrain was so worn in that it just didn't happen.
    Production Privee Shan

    B'Twin Triban 5
  • The Rookie
    The Rookie Posts: 27,812
    If you think about it, there is no derailleur to control where the chain goes when it's going backwards, the chain will tend to shift towards the middle of the cassette (in line with the chainwheel).
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • ilovedirt
    ilovedirt Posts: 5,798
    Yeah, I figured that afterwards, maybe it's more likely to happen with the closer spacing of 10sp? It just didn't happen on my old drivetrain
    Production Privee Shan

    B'Twin Triban 5
  • danlikesbikes
    danlikesbikes Posts: 3,898
    Find it common if spinning the cranks backwards whilst cleaning the chain, don't think its too much to worry about.
    Pain hurts much less if its topped off with beating your mates to top of a climb.
  • bennett_346
    bennett_346 Posts: 5,029
    Mine is ten speed and works fine backpedalling. It has to, some stuff i do requires a bit of back spinning.
  • bikaholic
    bikaholic Posts: 350
    It means that the chainrings are too far outboard.

    Adjust the chainline and/or reduce the size of the largest rear cogs and/or front chainring.
  • nicklouse
    nicklouse Posts: 50,675
    bikaholic wrote:
    It means that the chainrings are too far outboard.

    Adjust the chainline and/or reduce the size of the largest rear cogs and/or front chainring.
    no it does not mean that.

    yes having the chain line incorrect can result in that but it works both ways. bring it in and the chain "could" do the "same" on the "small" cogs.

    but the most common issue is people just dont normally do this. and more so when they get a new bike but when they change to new kit they expect everything to work as it was before which it will not do.
    ilovedirt wrote:
    Yeah, I figured that afterwards, maybe it's more likely to happen with the closer spacing of 10sp? It just didn't happen on my old drivetrain
    How would closer spacing do that? it has no effect on it. andthe cog is in the same place as the old one.

    it just that it is new.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • bikaholic
    bikaholic Posts: 350
    nicklouse wrote:
    bikaholic wrote:
    It means that the chainrings are too far outboard.

    Adjust the chainline and/or reduce the size of the largest rear cogs and/or front chainring.
    no it does not mean that.

    yes having the chain line incorrect can result in that but it works both ways. bring it in and the chain "could" do the "same" on the "small" cogs.

    Try it and see.
  • cooldad
    cooldad Posts: 32,599
    bikaholic wrote:
    nicklouse wrote:
    bikaholic wrote:
    It means that the chainrings are too far outboard.

    Adjust the chainline and/or reduce the size of the largest rear cogs and/or front chainring.
    no it does not mean that.

    yes having the chain line incorrect can result in that but it works both ways. bring it in and the chain "could" do the "same" on the "small" cogs.

    Try it and see.
    Seriously? Fart around with cassette and chainring sizes to try and achieve something totally pointless?
    Think about it - the chainline is only ever going to be 'perfect' on one cog - whichever one it is the chain will naturally gravitate to that one.
    I don't do smileys.

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  • spuddle
    spuddle Posts: 61
    Happened on my 1x10 setup with a directional shimano chain, when the chain wore out got a KMC none directional one and didn't do it anymore.