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  1. #1
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    Am I expecting too much from my FD?

    I just switched my cranks from the standard 22-32-44 to a 2x9 setup with 24-36 rings and a 12-34 9 speed cassette and the gearing works really well for where I ride. I also moved a BB spacer from the drive side to the other side for a more even chainline.
    One thing I was hoping to achieve was to set up my '08 XTR FD to allow use of the full range of the cassette without rubbing when on the 36 ring, but am I expecting too much of the FD? I've tried mounting it at various heights and I've got the outer plate of the cage parallel with the outer chainring per the setup instructions. I get the best range with it set where it was with the 3x9 rings (makes sense since that's what it's designed for), but I can't get it set to where the chain doesn't rub at one extreme and not the other. Is that likely to be the case with any FD or are there ones that handle a slightly wider span? Is there some setup trick that might help?
    It's no big deal if it just can't be done, I'll just keep trimming as needed with the front shifter (SRAM Attack twisty), but I wanted to find out if I'm trying to do something that just won't work.
    We don't stop playing because we grow old; we grow old because we stop playing.

  2. #2
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    With typical length chainstays the range of angles for the chain coming off the cassette is too great for any one position of the FD cage. That's why some brands (such as Sram) don't truly index the FD, opting instead for a trimmable micro-ratchet system.

    If it's only marginal, you might try flexing the cage a bit wider than stock, but be carefull as many of the cages are made of an overly hardened steel and might crack before they bend. Otherwise either live with it or consider adding an in-line barrel cable adjuster to use for trimming.
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  3. #3
    Edibles
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    I use Grip Shift for my FD and XO thumb for the rear.I got so tired of the rubbing,now the bike is Price Line stealth
    My oem parts 14 screws 3 plates and two hip replacement.I hope that's enough upgrades.

  4. #4
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    try a 10 speed chain.. its a little narrower, shifts fine on 9spd.

  5. #5
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    Quote Originally Posted by FBinNY
    With typical length chainstays the range of angles for the chain coming off the cassette is too great for any one position of the FD cage. That's why some brands (such as Sram) don't truly index the FD, opting instead for a trimmable micro-ratchet system.
    That's pretty much what I figured. I'm using SRAM Grip Shifters so I can "trim" by kicking the shifter down a notch when I'm on the inner cogs of the cassette. There's a lot of quick terrain changes where I ride and frequent shifting over the whole range of the cassette so the trimmer can be a pain at times.
    I did some drive train adjusting in a parking lot at work today and I've got it just about right by turning the FD on the seat tube a bit so the bottom of the cage kicks out a degree or two. That seems to give just enough clearance when on the outer cogs and because the inner surface of the cage is closer to the center of the seat tube, rotating the FD didn't move it out as much. Seems to work well in the parking lot, but I'll see how it is on the trail before I'm satisfied that it's gonna work.
    We don't stop playing because we grow old; we grow old because we stop playing.

  6. #6
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    You should be able to get the small ring to work with most of the large cogs, and the big ring to work with most of the small cogs, with no rubbing. And you should not spend much time in the big-big or small-small combos anyway, as that is cross-chaining and is really hard on the drivetrain and the sign of an unskilled hack rider.

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