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  1. #1
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    nrs ghost shift under load????

    01 nrs ghosts shifts under load. brand new drive train ... XT, XTR chain TRUVATIVE STYLO CRANKSET.... what now??? deal with it? or is there a simple fix?

    thanks, ben

  2. #2
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    maybe post up a photo of your cabling, particularly the outer cabling as it passes from the toptube to the seatstay.

    are the ends of the outer cables firmly and fully inserted into the frame lugs? any slop there can lead to probs.

    [size=1]
    - Giant NRS Composite - Giant XTC2 - Giant TCRCzero - Giant OCR1 -
    [/size]
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    [/size]

  3. #3
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    The NRS design "tops-out" the suspension during hard pedaling (giving it that hardtail
    like snap) This can also add slight tension to the rear derailleur cable causing ghost shifting.

    Slightly decrease the cable tension at the barrel adjuster on the shifters, or on the derailleur.

    Or, possibly due to cable routing, tension may be going slack slightly - in this case
    just add a bit of tension with the adjuster.

    Either way, it is definitly a cable tension adjustment problem.

    I used to have a ghost shifting NRS myself, but it's smooth running now

  4. #4
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    One more thought

    Quote Originally Posted by deoreo
    The NRS design "tops-out" the suspension during hard pedaling (giving it that hardtail
    like snap) This can also add slight tension to the rear derailleur cable causing ghost shifting.

    Slightly decrease the cable tension at the barrel adjuster on the shifters, or on the derailleur.

    Or, possibly due to cable routing, tension may be going slack slightly - in this case
    just add a bit of tension with the adjuster.

    Either way, it is definitly a cable tension adjustment problem.

    I used to have a ghost shifting NRS myself, but it's smooth running now
    If possible, make these adjustments from the barrel adjuster on the shifter while riding. Saves a lot of time getting off the bike, adjusting the barrel on the derailler, get back on the bike, skips again, repeat process, etc., etc.

    Get my point?

    Bob
    'If Wal-Mart sold parachutes, who would jump?' Frank Havnoonian (quoting his father) Drexel Hill Cyclery

  5. #5
    bang
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    Quote Originally Posted by laackund
    01 nrs ghosts shifts under load. brand new drive train ... XT, XTR chain TRUVATIVE STYLO CRANKSET.... what now??? deal with it? or is there a simple fix?

    thanks, ben
    i have heard the rear end on the earlier model NRS' are flexy, which changes the cable tension (the cable stops on the seatstay either get closer or farther away). try running full housing from the back of the top tube all the way to the derailer, and make sure the loop at the end of the seat stay to the derailer is big enough. 2004 model NRS' had full length housing just as i described for whatever that's worth.

  6. #6
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    i have an 01 nrs and it is very flexy (and creaky when dirty). but i've never had a problem with ghost shifting. instead i have a problem with the chain falling off the small chainring when riding over rocky terrain. even with the limit screw set correctly and plenty of tension on the chain, it will fall off if i'm bouncing around enough.

  7. #7
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    To add to the numerous good points;

    full length RD cable housing has been a fix as reported by some

    changing to a SRAM shifter/RD combo has also had good results

    NOT saying that either will/won't work, but something to look into when the other options are un-successfully exhausted.
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  9. #9
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    What about the other years? Did Giant only have this problem with the early year's? I know about the difference's with the dropout locations, but what about the rest of the seatstay?

    Don't get me wrong - I believe what you say, that's why I posted what I did. I just wanna know about the rest of the line. I'm still learning about it.
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  10. #10
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    Quote Originally Posted by AndrewTO
    What about the other years? Did Giant only have this problem with the early year's? I know about the difference's with the dropout locations, but what about the rest of the seatstay?

    Don't get me wrong - I believe what you say, that's why I posted what I did. I just wanna know about the rest of the line. I'm still learning about it.

    Giant changed the rear end design in '04. I haven't heard much about ghost shifting issues after the change so it's likely that the seatstay has been stiffened up. If you have one of these later models but still have ghost shifting issues, it would be easy enough to temporarily bypass the seatstay housing stops just to check it out.

  11. #11
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    Quote Originally Posted by angryasian
    Giant changed the rear end design in '04. I haven't heard much about ghost shifting issues after the change so it's likely that the seatstay has been stiffened up. If you have one of these later models but still have ghost shifting issues, it would be easy enough to temporarily bypass the seatstay housing stops just to check it out.
    interesting. i have an '05 NRS, otherwise the same as the '04. the outer cable/housing is already 1 piece, from the toptube all the way to the RD, so it seems Giant addressed this issue with the exact fix that's been suggested.

    a quick look through the Giant archives of NRS's, and indeed the pre-'04 models feature a 2-piece outer cable housing: toptube->seatstay and seatstay->RD.

    [size=1]
    - Giant NRS Composite - Giant XTC2 - Giant TCRCzero - Giant OCR1 -
    [/size]
    [size=1]- nothing stock here - move right along now -
    - Geelong area, Australia -
    [/size]

  12. #12
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    If this is the case, how is it that on my 2001 NRS I had to decrease cable tension
    to eliminate the ghost shifting?

    Set up normally, I had no problem on flat, rolling terrain, but any significant steep
    caused ghost shifting.

    I have a very steep granny ring hill in my back yard, so I could really get to the
    bottom of this problem. While pedaling up this hill, I could actually watch the
    cassette and see the chain want to skip to the next lowest gear (ie: up the cassette).

    So I had to slightly decrease the cable tension, since I did that it has since worked
    perfect.

    My take on this, (but I am not an engineer) is that because pedaling forces try
    to top out the suspension, the seatstay is bowing, but the cable stops are
    being pulled apart - think of the dropout being pulled towards the seat tube.

    So I still say, try the cable tension first, but a full outer rear cable is also a solution.

  13. #13
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    Thanks for the comparison guys! I know what to expect now and how to fix it if it become's a problem ..... buy more stuff.
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  14. #14
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    sorry it took so long to answer replys, out of town for the weekend.... anyway, after reading posts this morning i checked it out in the kitchen. i locked out the fork and brakes; when i stood on the pedals and tried to drive them forward, i could see the chain stay bowing outward a little bit. it seemed to be the most pronounced at the pivot below the cassette. the non drive side bowed some too, but it didnt appear to as much. after taking off the wheel and dismantling half of the rear triangle, i isolated that pivot to look for any play. no lateral movement, seemed to move in intended direction w/o any extra friction.... i havent tried the full length housing yet, would you suggest just using zip ties to keep it in place? also i dont have a digital camera, but ill see what i can do about borrowing one.

    thanks for the help... hopefully this helps narrow things down

  15. #15
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    Quote Originally Posted by laackund
    sorry it took so long to answer replys, out of town for the weekend.... anyway, after reading posts this morning i checked it out in the kitchen. i locked out the fork and brakes; when i stood on the pedals and tried to drive them forward, i could see the chain stay bowing outward a little bit. it seemed to be the most pronounced at the pivot below the cassette. the non drive side bowed some too, but it didnt appear to as much. after taking off the wheel and dismantling half of the rear triangle, i isolated that pivot to look for any play. no lateral movement, seemed to move in intended direction w/o any extra friction.... i havent tried the full length housing yet, would you suggest just using zip ties to keep it in place? also i dont have a digital camera, but ill see what i can do about borrowing one.

    thanks for the help... hopefully this helps narrow things down
    Some have suggested using either zip ties or opening up the cable stops with a dremel. Myself I can't say because I don't have much time with this mod, but i'm trying the zip-tie method first simply because I don't like permanent mod's unless I know they're worth it (my weight and riding style may not necessitate this mod for all I know).

    Cable, housing and zip tie can all be had for cheap - especially if you snagged a couple of zip tie's while you were in the kitchen.
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