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  1. #1
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    Ghost Shifting on jumps

    I'm having a problem with ghost shifting on small jumps. Whenever I try to jump a curb or something small like that my rear derailleur shifts for a second and then goes back to where it was before. I'm assuming it has to do with the cage on the rear derailleur letting up too much chain slack either when I jump or land. Anyway, has anyone had this problem and knows how to fix it? Is it possible my chain's too long? Thanks.

  2. #2
    pronounced may-duh
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    Do you have grip shifters? If so I think you may be rotating them slightly when you jump.

    Do you have a full suspension bike? If so It may be that the cable housing is being bent when the suspension moves.

    Can't really fix either of those.

  3. #3
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    good thought

    Quote Originally Posted by Maida7
    Do you have grip shifters? If so I think you may be rotating them slightly when you jump.

    Do you have a full suspension bike? If so It may be that the cable housing is being bent when the suspension moves.

    Can't really fix either of those.
    Yes I have grip shifters, no it's not a full suspension bike. It might be the grip shifters but it seems like the chain shifts to the different gear for a few seconds after my hands are off of the shifters. Good thought though.

  4. #4
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    Quote Originally Posted by dagimp
    Yes I have grip shifters, no it's not a full suspension bike. It might be the grip shifters but it seems like the chain shifts to the different gear for a few seconds after my hands are off of the shifters. Good thought though.
    This is one of the reasons I hate grip shifters. It's too easy to accidently rotate the shifter while just riding. Also It's hard to reach the brake levers with the damn shifter in the way. Lastly I find it very uncomforatble to ride with half your hand on this emormous lump of a shifter. Aaarg I hate gripshift.

  5. #5
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    my bike ghost shifts on jumps and large bumps when I am doing DJ and standing/mashing.

    I have triggers on my Specialized Hardrock Pro Disc.

  6. #6
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    Shortening the chain might help here. A shorter chain causes the derailuer to put more tension on the chain, also less chain length/weight slapping around. If you're running 3 chainrings up front, try shortening the chain down to where you have just enough chain to run the big ring on the smallest 3 cogs. Beyond the smallest 3 cogs, you're ovelapping gearing anyways, so any more chain than that isn't needed. If you're running 2 rings and a bash ring, shorten the chain so there's just enough to use the middle ring with the big cog in the rear. Also, if you're only running 2 rings up front, you can use a short-cage rear derailuer and shorten the chain some more, which will help keep the chain tighter.

    I have grip shift and have no problem with accidentally shifting it. Try holding the grip instead of the shifter when you don't want to shift it, or just be consious of what your hand is doing and don't twist it .

  7. #7
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    Quote Originally Posted by SoCalDesertRider
    Shortening the chain might help here. A shorter chain causes the derailuer to put more tension on the chain, also less chain length/weight slapping around. If you're running 3 chainrings up front, try shortening the chain down to where you have just enough chain to run the big ring on the smallest 3 cogs. Beyond the smallest 3 cogs, you're ovelapping gearing anyways, so any more chain than that isn't needed. If you're running 2 rings and a bash ring, shorten the chain so there's just enough to use the middle ring with the big cog in the rear. Also, if you're only running 2 rings up front, you can use a short-cage rear derailuer and shorten the chain some more, which will help keep the chain tighter.

    I have grip shift and have no problem with accidentally shifting it. Try holding the grip instead of the shifter when you don't want to shift it, or just be consious of what your hand is doing and don't twist it .

    Be very careful shortening your chain. If you acidently shift into the big cog in front and the big in the rear you may not have enuf chain and could snap off your rear derailer. Chances are your chain is it's length for a reason.

    SoCalDR, When your holding the grip instead of the shifter, how do you reach the brake lever? I hate grip shift!


    Standard 235: Sounds like something is off. Is your hanger or rear derailer bent? Is your rear derailer in perfect adjustment? Is your chain old, worn, dirty, rusty, dry, etc...? Do any of your cogs and chainrings have broken or bent teeth? Did you recently replace one piece of your drive train and not the other componenets? Like did you replace an old chain and leave your worn out gears? If you can't answer all these questions I suggest reading some books about bike maintenance and or taking it to a shop. Could be something easy like a frozen link in your chain.

  8. #8
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    You might want to also check your cables and housing. My bike used to do that, i have sram triggers and sometimes when i would shift it would't even do anything. Or if i was pedaling all of a sudden it would shift. The metal wires in the housing around my rear derailleur was coming out and getting all screwed up. I changed it out and it fixed all my ghost shifting problems. Actually it starting to do it again after 1 month after i replaced the housing. I need to figure out what im doing wrong becasue ive always installed cables and housing that until recently the metal wires have been coming and splitting out.
    -sam
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  9. #9
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    I would like to shorten my chain and my chainline is a bit off so I would like some spacing on my BB...

    Anyways, it's cranks that were like new when I out them on, a BRAND NEW Sram chain, and the stock IG50 cassette.

    I want to put my SRAM PC990 cassette on it, but I can't break that damn IG loose. Any suggestions?

  10. #10
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    Quote Originally Posted by Maida7
    SoCalDR, When your holding the grip instead of the shifter, how do you reach the brake lever? I hate grip shift!
    I like grip shift ...

    I'll describe my shifter/brake setup first (similar setup on 2 bikes) --- I run the grip shift on the rear derailuers only on both bikes. One bike is 1x9 (only one sprocket up front), so no front shifter or derailuer. The rear shifter is on the right as normal. The other bike is normal 3x9 and I use an old-school top-mount thumb shifter for the front derailuer. On both bikes, I run the front brake on the right side (which I'm used to from riding motorcyles- brake right, clutch left), so the front brake lever runs together with the rear grip shifter on both bikes. The rear brake is on the left. On both bikes, I use a normal-length grip on the left and a gripshift-length (short) grip on the right.

    I have just enough lever reach around the gripshifter using Hayes HFX Mag hydraulic levers (normal-length 2-finger levers, as far as I can tell) to do 1-finger braking on the front brakes when my hand is on the grip. Part of my index finger and thumb rest on the edge of the grip shifter, the slim part, so it doesn't bother my hand. I don't like gripping the inner bulbous part of the grip shifter, it makes my hand sore. On the left side, I use normal 2-finger braking on the rear brakes. I'm also used to being concious of not 'accidentally' twisting the right grip from time spent riding motorcylces and atv's with twist throttles. Hard twist at the wrong time and end up on the ground .

  11. #11
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    to get the most out of you levers

    I've found out by trial and error, how to get the most reach out of your brake levers. I use Avid mech speed dials which are pretty long. Move them as close to the grip shifter as possible. Then bring them back towards the handlebar so they're as close to parallel to the handlebar as possible then adjust them however you like. This will usually get you enough lever beyond the grip shift to use at least one, probably two fingers on the lever. You can of course try to cut your grip shifters. Sounds bad and you do it at your own risk but there's no reason why it wouldn't work fine as long as you don't cut the cable connection point.

  12. #12
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    Quote Originally Posted by dagimp
    I've found out by trial and error, how to get the most reach out of your brake levers. I use Avid mech speed dials which are pretty long. Move them as close to the grip shifter as possible. Then bring them back towards the handlebar so they're as close to parallel to the handlebar as possible then adjust them however you like. This will usually get you enough lever beyond the grip shift to use at least one, probably two fingers on the lever. You can of course try to cut your grip shifters. Sounds bad and you do it at your own risk but there's no reason why it wouldn't work fine as long as you don't cut the cable connection point.

    This is dumb. I want to be able to reach the levers comforatbly with at least 2 fingers. One finger braking is just not enough for me. The shifers are just in the way. Its a bad design and thats why I don't use gripshifters.

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