Gear problem.

freehub
freehub Posts: 4,257
edited October 2009 in Workshop
Hi.

For some reason when I back pedal the chain seems to end up slipping down to a smaller cog, the gear change seems smooth, could this be the sign of a new chain on an old cassette? I can push hard in big gears and I see no evidence of skipping.


Thanks
Will.

Comments

  • flasher
    flasher Posts: 1,734
    don't pedal backwards.
  • freehub
    freehub Posts: 4,257
    Flasher wrote:
    don't pedal backwards.

    Yes that would be the obvious soloution..... But the fact it does it means something is not configured correctly or could point to something need replacing, and I'm not happy using bicycle that is running **** or sounds like cack.
  • nicklouse
    nicklouse Posts: 50,673
    nope it happens as it is not designed to work that way.

    Please change whatever you wish but it may not change a thing.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • freehub
    freehub Posts: 4,257
    That's odd, because it's never done it before, at all, so I don't actually think it's normal :\
  • ride_whenever
    ride_whenever Posts: 13,279
    more likely a sticky freehub
  • freehub
    freehub Posts: 4,257
    How does that cause the chain to slip down to smaller gears when back pedalled? I am having freehub issues and freehub problems have being the worse problems I have ever had, but I don't notice the cassette stopping spinning.
  • desweller
    desweller Posts: 5,175
    I think you may have (very slight) cable issues. If it's upshifting on backpedalling add a little tension (rear mech barrel adjuster anti-clockwise) at a 1/4 turn a time to correct the derailleur alignment. If it's not shifting under load though I wouldn't worry about it.
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  • Bhima
    Bhima Posts: 2,145
    Does it happen when in the big ring and one of the larger 2/3 sprockets?

    If so, this is normal.

    It only happens to me when on the 50 x 25, which i'm never on anyway.

    Someone in a bike shop explained it to me ages ago - something to do with it being an extreme chain line.
  • crankycrank
    crankycrank Posts: 1,830
    Basically your derailleur is lined up with the sprocket that it's intended to guide the chain onto. When pedaling backwards the chainline is most often at an angle which can feed the chain off the sprocket. Now as you said that doesn't happen with every bike but it's not uncommon either. It could be because of different chainstay lengths, chainring or cassette sizes and some drivetrains are just set up better than others.
  • freehub
    freehub Posts: 4,257
    I'll just ride it see what happens, but I am 10000000% sure it is not normal as it's NEVAR happened before, on any bike I have had, all 3 of my road bikes had 105 mechs..

    I'm usually in the top 3rd cog for setting off and even then it used to be fine.
  • John.T
    John.T Posts: 3,698
    Have you just fitted a new chain. If so it may be one that is designed for 'easier changing', that is it can move between the cogs easier. This will work in both directions so if the chain is out of line when you back pedal it will ride on to the next cog. As others have said, if it works OK when riding I would not worry, it may bed in anyway.
  • freehub
    freehub Posts: 4,257
    It's a new chain yes but the same type of chain as I had on before, a 105 5600, unless they've changed them slightly since 2007. It's just an inconvinience sometimes at lights I back pedal to get in the best position for my left leg so I can push off better.
  • keef66
    keef66 Posts: 13,123
    It is all to do with chain line. When pedalling forwards the rear mech guides the chain precisely on to a particular sprocket. In reverse the chain is coming from the chainring with very little guidance, and will have a tendency to seek a better chainline - usually onto a smaller sprocket. It would be most likely when you're in the big chainring and on the bigger rear sprockets. Fitting the new chain on a part worn cassette may be part of the reason and it may bed in as the chain wears
  • New chain....old block[cassette]

    There's your problem...I always replace like for like...new chain with a new block
  • amaferanga
    amaferanga Posts: 6,789
    New chain....old block[cassette]

    There's your problem...I always replace like for like...new chain with a new block

    I prefer only to spend money if I really need to. You don't necessarily need a new cassette with every chain change. Of course if you don't replace your chains often enough then you accelerate wear on the cassette and you do need a new cassette....
    More problems but still living....
  • freehub
    freehub Posts: 4,257
    New chain....old block[cassette]

    There's your problem...I always replace like for like...new chain with a new block

    Is it deffo the cassette though? I'm not into spending money for the sake of it, as I said, pedaling, putting lots of power through, the chain does not skip, at all, I replaced the chain when it got to 1% wear limit, I think it's 1%.

    The thing I am trying to find out, is it never, did it before, on the same gear.
  • lee337
    lee337 Posts: 17
    freehub wrote:
    I'll just ride it see what happens, but I am 10000000% sure it is not normal .

    No, at the most you are 100% sure.
  • John.T
    John.T Posts: 3,698
    Just ride it Will. It will probably go away.
  • Check your chain for a stiff link
  • Barrie_G
    Barrie_G Posts: 479
    you also say you're having free hub problems, try taking the back wheel off the bike and check to see that the cone nuts are done up.

    I recently had to remove my back wheel after a visit from the P*(^&^&%% fairy and the nuts had slacken a little allowing some movement of the free hub, if this is the case it is possible that the free hub is moving enough to allow engagement of a different gear.
  • freehub
    freehub Posts: 4,257
    It's not the nuts, I've had the freehub off the bike and the bearings out. The only way to fix it is a new freehub I think, but I can't afford 35 quid so I'll ride it till it dies.
  • redddraggon
    redddraggon Posts: 10,862
    freehub wrote:
    I can't afford 35 quid

    is it just because you are from Yorkshire?
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  • MrChuck
    MrChuck Posts: 1,663
    My gears are currently doing the same thing, but they work fine the right way so at the moment I don't care.
    Agree that changing the chain is probably the biggest culprit: I took mine off when my chain checker told me to put a new one on, but when the new one slipped (3rd one on that cassette I think) I put the old one back on (maybe other way around or something), and this behaviour appeared.

    So, I wouldn't worry about it as long as everything works fine while you're actually riding.
  • freehub
    freehub Posts: 4,257
    freehub wrote:
    I can't afford 35 quid

    is it just because you are from Yorkshire?

    I'd spend more than you ever dare imagine if I had a part time job.. I'd have a bike that makes your's look like a old hack.
  • redddraggon
    redddraggon Posts: 10,862
    Mine is an old hack
    I like bikes...

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  • freehub
    freehub Posts: 4,257
    No, I mean the new one you are building.
  • redddraggon
    redddraggon Posts: 10,862
    freehub wrote:
    No, I mean the new one you are building.

    My Scott Addict, with SRAM Red, and Lightweight Obermayers?
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  • freehub
    freehub Posts: 4,257
    Yea.
  • rake
    rake Posts: 3,204
    edited March 2010
  • freehub
    freehub Posts: 4,257
    But it does not do it on all cogs. Apart from that it's running fine though, I replaced the chain when it got to 1%