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  1. #1
    Senior Member Notso_fastLane's Avatar
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    Derailer issues.

    This might be better in the Bicycle mechanics section, but it's recumbent specific, so I thought I would try here first.

    I have a TW-Bents Elegance model, (specifications here)
    Shifter : Sram grip shifter.
    Stem : alloy adjustable stem.
    F/derailleur : Shimano 105
    R/derailleur : Shimano XT
    Crank : 52/42/30 w/chain cover, alloy
    Freewheel : Sram 970 11-34 9 speed
    Chain : KMC Z9000
    With the factory setup, after taking it to my LBS when I first got it for set up and installing some things, the LBS mechanic said they can't get all the gears in the range to work. I'm guessing there is something wrong with the way he adjusted the shifter or the derailer, but I don't want to make it worse.

    So I'm going to go read the Park Tools website, and Sheldon Brown's site, but if anyone has any suggestions from the bent riders specifically, I'd love to hear 'em.

    Currently, there are two issues: On the smallest front sprocket, the rear derailer goes into the lowest (1st) gear one click early (when it should be in the second cog), and if I shift into 1st, the chain actually comes off and into the wheel. Secondly, the gear won't go into the highest (9th) cog on the rear. This makes me think the whole thing is miscalibrated by one gear somehow, but I haven't figured out how to fix it.

    Thanks!

  2. #2
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    My first question would be did it ever work properly? Is this a new or used bike?
    If it is new, or used but worked before, I would check to see if the derailleur hanger is bent.

    If not, then it sounds like the hi and lo limit screws may not be adjusted properly.

    It should never go off the end past the big cog. The lo limit screw needs to be screwed in.

    If you unclamp the shift cable at the derailleur, will it go onto the small cog? If not then the hi limit screw needs to be backed out.

    I would suggest that you go to the Park tool website and go through the rear derailleur setup process. (and if you are able to get it working, I would find another LBS!)

    (All this is assuming that your cassette spacing is compatible with SRAM shifter pull ratio, and that the cable is run properly onto the clamp on the rear derailleur.)

  3. #3
    Senior Member BlazingPedals's Avatar
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    It sounds like it's adjusted a gear off. Here's how I would do it.

    1 Shift the chain onto the second-largest cassette gear.
    2. Put the shifter on 2nd gear but don't actually perform the shift by pedaling.
    3. Using the coarse adjustment barrel (at the derailleur,) adjust the cable tension so that the top jockey pulley is centered to the cog the chain is on (#2.)
    4. Shift the chain to 1st gear.
    5. Adjust the low limit screw so that the chain can't go past 1st gear and into the spokes. That is, screw it in until you just start to get resistance.
    6. While you're in 1st gear, adjust "b" screw, which is up by the main pivot, so the top pulley is close but not riding on the cassette gear. <1/2"? Not sure the exact spec. Probably *most* of the way screwed in for an 11-32 cassette.
    7. Shift to high gear and adjust hi limit screw so you can't shift the chain into your frame.
    Now test all the gears up and down. Should work, possibly with a few tweaks using the fine adjustment barrel adjusters at the handlebars. Won't downshift well enough = screw the adjuster CCW a click at a time, clunks hard when upshifting = CW a click.

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    The first time I took my trike to a cycle shop for gear adjustment, they insisted it was the wrong kind of derailleur because there was no way to get it to work smoothly. After my husband and I beating our heads on it for a while, I took a bunch of pictures to send to the ICE people. In less than half an hour, they wrote back that the shifter cable had been threaded around the screw in the wrong direction. I'm sure you've looked into that, but I was stunned that such a little thing could cause such a big headache.

  5. #5
    Senior Member Notso_fastLane's Avatar
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    I haven't really had a chance to look at it closely. Thanks for the info. I've got the Park Tools stuff printed so I can have the instructions with me. I wasn't sure if there was anything unique to recumbents with the longer chain that I need to worry about.

    I'll post an update when I get a chance to tinker with it (probably not this week).

  6. #6
    Insane Bicycle Mechanic Jeff Wills's Avatar
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    If you have the time, take the bike down to Angle Lake Cyclery, down by SeaTac. They know bike mechanics and they know 'bents.
    Jeff Wills

    All my bikes.

  7. #7
    Senior Member Retro Grouch's Avatar
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    I can think of a number of things that might make it do that. If it was my bike the first thing that I'd do would be to check the derailleur hanger alignment. If that checked out I'd completely disconnect the shift cable and reinstall the derailleur as if I was doing it for the first time.

  8. #8
    Senior Member Notso_fastLane's Avatar
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    Quote Originally Posted by Jeff Wills View Post
    If you have the time, take the bike down to Angle Lake Cyclery, down by SeaTac. They know bike mechanics and they know 'bents.
    Now that I've got my bike rack, I might do that this weekend....since I'm driving all the way down to Vancouver to pick up a new (to me) motorcycle anyway.

  9. #9
    Insane Bicycle Mechanic Jeff Wills's Avatar
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    Quote Originally Posted by Notso_fastLane View Post
    Now that I've got my bike rack, I might do that this weekend....since I'm driving all the way down to Vancouver to pick up a new (to me) motorcycle anyway.
    Dang, if I weren't already committed (well, my wife says I should be...) I'd say bring it on by and I'll fiddle with it a while.
    Jeff Wills

    All my bikes.

  10. #10
    Senior Member Notso_fastLane's Avatar
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    Quote Originally Posted by Jeff Wills View Post
    Dang, if I weren't already committed (well, my wife says I should be...) I'd say bring it on by and I'll fiddle with it a while.
    Thanks!

    Quote Originally Posted by BlazingPedals
    It sounds like it's adjusted a gear off. Here's how I would do it.

    1 Shift the chain onto the second-largest cassette gear.
    2. Put the shifter on 2nd gear but don't actually perform the shift by pedaling.
    3. Using the coarse adjustment barrel (at the derailleur,) adjust the cable tension so that the top jockey pulley is centered to the cog the chain is on (#2.)
    4. Shift the chain to 1st gear.
    5. Adjust the low limit screw so that the chain can't go past 1st gear and into the spokes. That is, screw it in until you just start to get resistance.
    6. While you're in 1st gear, adjust "b" screw, which is up by the main pivot, so the top pulley is close but not riding on the cassette gear. <1/2"? Not sure the exact spec. Probably *most* of the way screwed in for an 11-32 cassette.
    7. Shift to high gear and adjust hi limit screw so you can't shift the chain into your frame.
    Now test all the gears up and down. Should work, possibly with a few tweaks using the fine adjustment barrel adjusters at the handlebars. Won't downshift well enough = screw the adjuster CCW a click at a time, clunks hard when upshifting = CW a click.
    Thanks! All it took was adjusting the barrel adjuster at the grip! I also had to tweak the screw a little to get the derailer to sit a little lower, it was rubbing on the biggest cog in the rear. If you ever get up this way, first beer's on me!

    Not sure why the LBS was convinced that it had something to do with the 'long chain'. I'm thinking he didn't just feel like really working it. It took me less than ten minutes to get it all adjusted.

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