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2016 Stumpjumper gear problems

SousterSouster Posts: 12
edited December 2016 in MTB workshop & tech
Hi

Hoping you guys can help me please.

Having real problems with the gear on the rear of my 2016 specialized stump jumper fsr.

I've replaced the inner and outer gear cable, new rear shifter and it's running sram x9 rear mech and shifter.
Chain and cassette is perfectly clean. I've indexed the gears as per the videos on YouTube.

The symptoms are identical of a crappy gear cable, however it's brand new. Not all the gears are a problem, i usually can't get the lowest gear (1st) it trys to change for half a mile then changes. Then coming down the block into 3rd or 4th, it takes ages to shift back down. But the last half of the block changes fine. It's totally pointless having 10 speed when I can only get half the gears. I'm going to try a second cable but 99% sure it won't sort it.

Is it worth changing the rear mech? Or the cassette. Could it be the cassette been as the lower half of the block change OK?

Any advise would be great. Thanks

Posts

  • RockmonkeySCRockmonkeySC Posts: 14,770
    Have you checked that the cable runs smoothly when it's routed through the bike? It could be a routing issue causing drag on the cable.
    How worn are the chain and cassette?
  • cooldadcooldad Posts: 32,599
    Bent hanger or not ndexed properly.
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  • JBAJBA Posts: 2,820
    Why did you replace the shifter and cable on the bike?
    This may have some bearing on why you now can't get clean shifting.
    “Life has been unfaithful
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  • The RookieThe Rookie Posts: 27,757
    Opposite symptoms of crappy cable. Crappy cables stop it changing up gears (smaller sprockets) so if you can't get first it's just crappy indexing I suspect.
  • JBA wrote:
    Why did you replace the shifter and cable on the bike?
    This may have some bearing on why you now can't get clean shifting.

    Thanks for your replies guys.

    The bike has done very little miles. I bought it second hand, but all the moulding pips were still on the tyres. Unless they were replaced, but the rest of the bike is so good.

    I replaced the shifted due to breaking it not replacing the cable correctly. So it's ruled out the shifter and cable thinking about it, because the gears were terrible when I bought the bike too.

    I take it this is not the nature of the specialized stump jumper? There's an issue that needs fixing?

    If it was indexing, why would that cause an issue half way up the block?
  • cooldadcooldad Posts: 32,599
    Presumably by replacing the cable, you mean inner and outer?

    Then loosen everything off, read Parktools, and start from scratch, including limit screws.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • JGTRJGTR Posts: 1,404
    I use Parktools. Does sound like it maybe isn't set up that well, there's quite a few steps and the Parktools guide takes you through them all. What I did find is that you can get it spot on for the first few gears but as you go up the casette (small to big) you still need the adjust the cable for the bigger gears, which means you then mess up the smaller gears so you have to balance it across the casette if that makes sense? The main tool is your ears as you can hear when the chain is moving in and out of alignment. Also if you have a 2x make sure it's on the correct rings at the front. Basically use Parktools guide.
  • JGTRJGTR Posts: 1,404
    If it was indexing, why would that cause an issue half way up the block?

    In my experience ut can if the indexing and limit screw settings are not spot on.
  • The RookieThe Rookie Posts: 27,757
    You need to sort out your wording, first gear is lowest and the biggest sprocket, going up the gears is from biggest sprocket to smallest, just like in a car higher gear faster speed (for constant pedal speed).

    Erm, silly check, have you got the right number of speed shifter to match the cassette?
  • RockmonkeySCRockmonkeySC Posts: 14,770
    If you can get it right for one end of the cassette but not the other then there's a good chance the mech hanger is bent.
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