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  1. #1
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    Skipping gears one way, perfect the other, going crazy.. (VIDEO ADDED)

    Im at my wits end, ive tried EVERYTHING I can think of. Ive puled the rear cassette off and closely inspected it, taken off and thoroughly cleaned the chain, disassembled and cleaned the rear derailleur... same exact results...

    Shifting from Big down to small its perfect, never misses a beat..


    This is the adjustment issue Im running into.

    For the sake of explanation.. 1st is the smallest ring on the rear cassette, 9th is the biggest..

    shift al the way down to 1st.. shift up one click... nothing.. still on 1st... click again.. skips 2nd jumps to 3rd...

    adjust (tighten) so that it shifts from first to 2nd fine..

    shifts from 1st to second fine, from 2nd to third fine, then shifts from 3rd to 5th.. skips 4th..

    adjust (loosen) so it no longer skips 4th.. now Im back to it not shifting from 1st to 2nd again..



    thats the dilemma.. Ive spent over an hour and a half just turing and adjusting and I cannot get it so shift from 1st to 9th smoothly... no matter what..

    shifting from 9th to 1st is perfect..


    What on earth is causing this.. its as though the derailleur does not move enough per shift on the low end, then moves too much per shift at the top end of its travel..

    It hasnt been this way, and I havent changed ANYTHING recently, nor have I had andy damage done, everything is in great shape..

    Last edited by ja001son; 11-14-2012 at 10:51 AM.

  2. #2
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    If it's a Sram derailleur, back the b-screw out until it shifts properly.
    I can barely get my mouth around it.

  3. #3
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    Its not, its Shimano SLX.

    Stock components on the 2012 Spesh Camber Comp

    Ive removed the big chainring and went with a 2+bash in the front, I also removed a few lengths from the chain..

    I messed with it some more, its as though the derailleur just does not move enough per click when shifting smaller ----> larger. I guess maybe the shifter is crapping out? Bike is a few months old..

    I notice when its acting up Ill be on say 5th and shift one click up.. nothing happens... shift back down.. nothing.. back up.. nothing I look at the derailleur when Im doing this and its not even moving...

    I dont know if something is in a bind or what.. Im lost.

  4. #4
    inexperienced at large
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    Quote Originally Posted by Pedalphile View Post
    If it's a Sram derailleur, back the b-screw out until it shifts properly.
    Second on that. I hope this hair splitting experience ends in happy trail rides.

    Sent from my Desire HD using Tapatalk 2

  5. #5
    Ski N Bike Tech
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    Sounds like a bent derailleur hanger. Have a shop realign it if you don't have the proper tool.

    You should have the wheel trued first to make sure everything gets aligned properly.

  6. #6
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    Sounds like a bent derailleur hanger. Have a shop realign it if you don't have the proper tool.

    You should have the wheel trued first to make sure everything gets aligned properly.



    New wheels will be here friday, so Im not concerned with them.

    I do not have a shop option. The only local shop is a hole in the wall, They do not carry Specialized. I didn't buy the bike from them and Im not driving 240 miles round trip to have the shop I bought it from look at it.

    Any work done must be done by me, so What do I need to check the alignment?


    Mind You there has been no crash or damage and not a single thing has a scratch on it so I cant fathom how it has been bent,.

  7. #7
    Ski N Bike Tech
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    Quote Originally Posted by SkiNBike View Post
    Sounds like a bent derailleur hanger. Have a shop realign it if you don't have the proper tool.

    You should have the wheel trued first to make sure everything gets aligned properly.
    Also make sure the cassette lock ring is torqued properly, and that cable tension is proper.

  8. #8
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    Quote Originally Posted by SkiNBike View Post
    Also make sure the cassette lock ring is torqued properly, and that cable tension is proper.
    Ive pulled the cassette apart twice and reassembled, have no idea how to know its "torqued properly" its definitely tight.. It shifted fine before, nothing had been changed since..

    Nor do I know how to check for proper cable tension... Ive tightened it, loosened it.. neither seemed to help.... it worked fine before, nothing had been changed...


    Understand the reoccuring theme..

    NO CHANGES, NO CRASHES, NOTHING it just started doing this out of the blue in the middle of a ride

    No option to take it to a shop, none.

    Ive removed and inspected the chain, disassembled and cleaned the rear derailleur... neither had any effect whatsoever.

    The only thing I have not done is pulled apart the shifter, Ive tried using the adjustment knob to no avail..

    adjustment attempt goes as follows..

    not shifting... make tighter down shift and try shifting up again..

    still not shifting... make tighter, downshift and try shifting up again.. shifts this time..

    try next few gears.. overshifts.. skipping from 3rd to 5th..

    loosen, try again.. no longer skipping 4th.. 3rd to 9th shifts fine...

    back down to 1.. wont shift 1 to 2...

    tighten untill it will shift 1 to 2...

    shifts from 1 to 3 fine.. skips 4 jumps to 5...

    process repeats..

  9. #9
    Ski N Bike Tech
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    Park Tools DAG-2 is what you need.

    Parktool.com will be your friend if you don't want to take it to the local shop. It will help with home repair. Click on "Repair help" in upper right corner.

    If the bike is new, it will be cable tension as the cables have settled in. You will have to increase the tension until it shifts.

    Dérailleur hangers don't take much to get out of alignment. They are often made of soft aluminum as a way to save the frame.

  10. #10
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    A subtle bend to the hanger is usually characterised by some shift being ok, then getting progressively worse as you go on. Bigger bends may well be visible as you look at the derailleur cage in particular (should be vertical). A bent hanger can occur over time, with several small events contributing to a larger movement. It also could be that the hanger had a slight bend from new anyhow.

    When adjusting the gears, first check the high limit. You'll probably want to back off any adjustments you've done with the barrel adjustors so that the derailleur is in its natural position. In the high gear (small cog) the jockey wheel should sit perfectly below that cog. If thats ok, then start to change gears. Once again, check that for every change the upper jockey wheel is sitting precisely below the cog it should be in. This is where you'll be able to see if the adjustment is progressively becoming worse.

    Poor shifting could also be the fault of some gunk stuck in the gear outer. The last section before the RD is a classic place to end up with crud. You'd need to take that bit off the bike and the cable out to properly clean it if thats the case. You'll feel that the shifter is hard to operate, or feels sluggish.

    The last issue could be that the shifters have some issue going on. If you try every fix and there's still no joy, then the shop might be the only way out.
    Rimmer - "There's an old human saying - if you talk garbage, expect pain"

  11. #11
    Ride Responsibly
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    sounds like your cables are gunked up or rusted in the housings.

  12. #12
    the catalan connection
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    Quote Originally Posted by LWright View Post
    sounds like your cables are gunked up or rusted in the housings.
    I would say that too
    "Blessed is the man who, having nothing to say, abstains from giving us wordly evidence of the fact." George Elliot

  13. #13
    Just a flesh wound
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    Quote Originally Posted by What&son View Post
    I would say that too
    I would check your cable and housing. If the cable isn't moving properly, the shifting will be bad.
    My name is Chris and I ride a Prophet 650b with a Lefty.

  14. #14
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    Quote Originally Posted by What&son View Post
    I would say that too
    I wouldn't say that. He is having trouble while the shifter is pulling cable, not releasing cable.

    With the symptom described, the hanger would be the first thing to check.

  15. #15
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    Check the anchor bolt where the cable connects to the rear derailleur. If the cable gets routed on the wrong side of the bolt it can cause the exact symptoms you describe. I doubt this is it since you said it just started happening on its own but it might be worth a quick check.

  16. #16
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    Buy the dang DAG. Not having access to a shop you need one to properly tune a drivetrain. I can't tell you how many times me and my friends have had shifting problems like yours and it turned out to be a bent hanger. Hangers are designed to bend. I have bent them by picking up a stick in the rear dreaileur, hanging my bike on the wall with no rear wheel while mounting a tire, a friend laying my bike down on the deraileur side while taking a whiz, etc. Also could have bent it by taking out the links on your chain when you converted to two ring up front. If this is a full suspension bike when you compress the suspension the chain tightens. If you were in big big the chain may have gotten too short. Guess what the first thing to bend would be if this happens. You got it. The hanger.

    Oh, and also check that your rear wheel is seated evenly in the drop outs.

  17. #17
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    Here is a video of the issue..

    Note how when in the center of the cassette it misses a shift up, so I shift down, and try and shift up again and nothing happens.. the derailleur doesn't even move.


    Rear derailleur issue - YouTube

  18. #18
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    Quote Originally Posted by ncfisherman View Post
    I wouldn't say that. He is having trouble while the shifter is pulling cable, not releasing cable.

    With the symptom described, the hanger would be the first thing to check.
    You are quite right!
    But why not check the easy stuff?
    And you never know when some "Rapid-Rise" type situation might bite yer arse!

  19. #19
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    Took the shifter apart,.. the gears inside are plastic..... I sprayed some oil in there and that seemed to help a little (though I did not expect it to) ..

    I cant help but suspect the shifter, especially after seeing it not move the derailleur at all like that..

    They are Alivo shifters...

  20. #20
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    I suspected the shifter when I saw the video. It's the only root cause that makes sense to me.

    I realize a misaligned hanger can do weird things, however, it should not be able to make your derailleur refuse to move if the cable is being drawn up by the shifter. As J.B. Weld pointed out, however, you do need to be certain that the cable is correctly routed into the derailleur.

    Good luck,
    Pete
    I can barely get my mouth around it.

  21. #21
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    Quote Originally Posted by Pedalphile View Post
    As J.B. Weld pointed out, however, you do need to be certain that the cable is correctly routed into the derailleur.

    Good luck,
    Pete
    pic
    Attached Thumbnails Attached Thumbnails Skipping gears one way, perfect the other, going crazy.. (VIDEO ADDED)-dsc05401.jpg  


  22. #22
    chunk junkie
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    check to see if the wires in the SIS housing are pushing through the ferrules somewhere.

  23. #23
    Nouveau Retrogrouch SuperModerator
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    Quote Originally Posted by ja001son View Post
    pic
    Been there...

    Shift to the smallest cog.
    Disconnect the cable from the RD.
    Check and readjust the high limit screw.
    Reconnect the cable.

    And the hanger alignment should be checked.
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  24. #24
    Chamois Dropper
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    Looking at the video, it appears to me that the pawls in the shifter are not always engaging when you try to downshift. I have had this problem on old shifters with dried up hardened grease. It sounds like the shifter is clicking but not actuating the cable every time.
    2008 GT Force
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  25. #25
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    From the small, outermost cog, you should be able to make all the shifts by pulling on an exposed section of the cable. If it shifts good this way then you know the problem is not the derailleur.
    With the chain on the largest, innermost cog and NOT turning, you can pull the cable housing away from the shifter while shifting, should be able to feel each release and then each uptake as the housing moves.
    Have you checked out Park Tool Co. » ParkTool Blog

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