Results 1 to 6 of 6

Thread: Chain popping

  1. #1
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    63

    Chain popping

    Hey got a problem with my FS bike when i hit a step up 1 foot or higher and get the front whell up and start powering the back wheel up the chain starts poppin or ghost shifting.
    Not sure if coming frome front rings or from the casset but it is enough for me to lose power and not make the step up. Any help or suggestions would be cool.

  2. #2
    Jm.
    Jm. is offline
    mtbr member
    Reputation: Jm.'s Avatar
    Join Date
    Jan 2004
    Posts
    7,137

    We need to have a sticky/faq about chain skipping/popping

    and how it is related to chain stretch and the destruction of the rear cogs and front rings.

    Something like; "Why is my chain skipping/popping when I try to pedal up a steep hill with a lot of torque?"

    Because most likely your chain has stretched out. This means that your rear cogs have been stretched by the chain, and if this situation is bad enough, the front rings have been stretched by the chain as well. The actual gears don't "stretch", but they become smaller in shape and the metal material either packs up on one side, or it just leaves the teeth completely. This means that with a new chain, the teeth will not be spaced correctly, so you'll still get skipping and popping, maybe even worse than before. The only way to fix this problem is to get a new drivetrain, including a chain, cassette, and possibly rings. Because of how much torque you can exert on the smaller rings, they are the most likely to be destroyed, so the big ring usually gets by because of it's size (spreading out the force) and the fact that it's not used as often. Even still, it's possible to ruin all three of these.

    How do we prevent this? We change the chain frequently to prevent it from stretching and ruining all the gears. If someone wants to post a picture of them measuring the chainstretch with a ruler from the beginning of one link and 12" past, that would be great. Anything between 1/32nd and 1/16th of strech should be changed. 1/16th starts to get on the longer side of things and when you get to 1/8th you've usually ruined the cogs in the back at least.

    Due to how much torque you put on your bike while riding, this may mean that you only get 6 months out of a chain or less, but that turns out to be cheaper than replacing an expensive cassette and rings.
    I know in my heart that Ellsworth bikes are more durable by as much as double. AND they are all lighter...Tony Ellsworth

  3. #3
    Curtlo Hardtail(liatdraH)
    Reputation: liatdraH's Avatar
    Join Date
    Jan 2004
    Posts
    46

    I agree with JM

    There is a likelyhood that your chain is stretched, and if this is the case it is only a matter of time before you do ruin your cassette and/or your rings.
    From your description it also could be a section of housing that is too short on your FS frame. If the section of housing where your frame piviots is too short it will pull a little on your cable and cause a partial shift. When you are climbing these 1 foot climbs you are probably compressing your rear shock, with the housing the wrong length it could ghost shift.
    Rule books are paper they will not cushion a sudden meeting of stone and metal.

  4. #4
    Pedalphile
    Reputation: HPilot's Avatar
    Join Date
    Jan 2004
    Posts
    245

    Do and don't agree with the above

    Quote Originally Posted by Andy
    Hey got a problem with my FS bike when i hit a step up 1 foot or higher and get the front whell up and start powering the back wheel up the chain starts poppin or ghost shifting.
    Not sure if coming frome front rings or from the casset but it is enough for me to lose power and not make the step up. Any help or suggestions would be cool.
    True that, over time, your chain stretches and the cogs wear, BUT, I have a brand new drivetrain and this happens when in the 34 tooth rear and middle ring front. How new/old is your drivetrain? Depending on your rear suspension design, when the rear wheel moves through it's path of travel, tension on the chain changes. When you compress the rear and that path moves the rear tire up and forward, the tension decreases and may cause a jump or ghost shift. It happens to me on an XTR rapid rise rear that the chain moves down a gear and then back up under heavy torque and compression going up a hill with obsticles. Only when I'm in the gear combo listed above. I have been having issues with this combo since the beginning. I think it may have to do with the not so perfect chain line created by the new outboard bearing system BB. It is ticking me off and I am looking to find why I am still having issues with this gear combo.
    [SIZE=3]"A witty saying proves nothing."- Voltaire[/SIZE]


    Eric

  5. #5
    occupation : Foole
    Reputation: Fuelish's Avatar
    Join Date
    Dec 2003
    Posts
    2,545
    Quote Originally Posted by Jm.
    We need to have a sticky/faq about chain skipping/popping and how it is related to chain stretch and the destruction of the rear cogs and front rings.
    Something like; "Why is my chain skipping/popping when I try to pedal up a steep hill with a lot of torque?"
    I second Jm's motion......great idea !!!

  6. #6
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    63

    New question here. More info

    The bike is a Cannondale Gemini (no smart remarks abought crack in fail please) bike is only two months old so chain should be fine just started haveing problem last two rides ON National down here in AZ. Probllay just some type of adjustment ? but need some place to start. I can rebuild a fork but cant tune a derailuer worth a darn. Pretty funny Huh.
    Thanks for the info I well keep checking back. Also noitced on the last ride it happening when I put power into the pedals and the supension is compressing when hitting the step ups I was talking abought .

Similar Threads

  1. Should I shorten my chain?
    By Vulcan in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 6
    Last Post: 03-08-2005, 08:20 PM
  2. What do you use to lock up your bike?
    By LavaPunk in forum General Discussion
    Replies: 44
    Last Post: 02-06-2005, 12:20 AM
  3. Good info on bike locks.
    By 2melow in forum General Discussion
    Replies: 1
    Last Post: 02-06-2005, 12:02 AM
  4. Noisy chain when in middle ring- HELP!!!!!!!
    By HPilot in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 2
    Last Post: 02-01-2005, 09:49 AM
  5. popping and skipping chain.......
    By thejuru in forum Weight Weenies
    Replies: 5
    Last Post: 05-07-2004, 11:48 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •