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  1. #1
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    Suntour XC Comp BB size w/ STX-RC derailleur

    In 1995 I bought a Raleigh M400 w/ STX-RC (3x7 spd) components for touring down to Florida. I wanted taller gearing so the shop owner was nice enough to put on his Suntour XC Comp cranks which had bigger chainrings and didn't charge me. (68/122mm BB).

    I'm having a hard time getting it to downshift onto the small chainring because it looks like the chainring is too close to the seat tube (31.8) with the derailleur all the way in. Should I get a longer spindle BB to make this work or is this combination not compatable? It's been sitting for a while and I can't remember how it worked in 1995.
    Bill

    '95 Raleigh 400, STX-RC (road, touring)
    '00 Santa Cruz Superlight, XTR
    (Northern N.J.)

  2. #2
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    you loosened up the limit screw all the way? I don't think I've ever had that problem u describe

  3. #3
    Mantis, Paramount, Campy
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    The 122mm bb should be good with that crank.
    Two possible issues: One, front indexing sucks in general across all manufacturers lines. Two, the STX f derailleur is designed for smaller rings and the shaping of the cage might not line up quite right. You may need to bend the derailleur a bit to get it to move the chain.
    *** --- *** --- ***

  4. #4
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    Enough slack on the cable?
    Do you have extra adjustment room on the big ring side?
    Round and round we go

  5. #5
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    Limiter screw all the way loose and the derailleur almost touching the seat tube. I had the derailleur turned in a little to force the chain down.

    It did work on all three at one time.

    The big chain ring is kind of big for that derailleur though and I plan on riding it to figure out a better group up front. 28-39-52
    Bill

    '95 Raleigh 400, STX-RC (road, touring)
    '00 Santa Cruz Superlight, XTR
    (Northern N.J.)

  6. #6
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    Quote Originally Posted by Shayne View Post
    The 122mm bb should be good with that crank.
    Two possible issues: One, front indexing sucks in general across all manufacturers lines. Two, the STX f derailleur is designed for smaller rings and the shaping of the cage might not line up quite right. You may need to bend the derailleur a bit to get it to move the chain.
    ^^^^^probably this^^^^^
    stx would be for compact chainrings, you may want to try a roadbike front mech for the bigger chainrings, or an older vintage mtn front mech.

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