my chain wont stay on my sprocket or tensioner help!!

Discussion in 'Transmission / Drivetrain' started by sourdiesel404, Dec 2, 2013.

  1. sourdiesel404

    sourdiesel404 Member

    my chain keeps popping off my rear sprocket and tensioner and when I go to start it pulls tensioner in spokes help- please what do I do looks like its aligned

  2. bluegoatwoods

    bluegoatwoods Well-Known Member

    Well, this is an easy one. It can hardly be anything but your engine drive sprocket.

    You'll want to pull the wheel and have a close look at it. Make sure that the sprocket is centered on the axle and that it lies 'flat' with the wheel.

    Yup. It's a pain dealing with those sprocket mount bolts. But once you've got it right it stays in place.

    You'll want to make sure that chain tensioner is good and tight on the chainstay. Shim it with strips of inner tube if necessary.
  3. butterbean

    butterbean Well-Known Member

    Shimming with innertube is a bad idea, which I can attest to firsthand. When it gets wet, and it will in the rain or the snow, it will slip no matter how tight it is. Either shim with metal, or drill a hole in the front side of the tensioner bracket for a set screw.
  4. sourdiesel404

    sourdiesel404 Member

    what could I shim with? an the tensioner took out my spokes so I need new rim does that mean I need a new rear sprocket an the rubber mount also?
  5. crassius

    crassius Well-Known Member

    I saw off a piece of old handle bar about an inch or so long, then saw that in half to make two "C" shaped sections to shim with - also, if the bolts don't seem to be tightening without stretching, I replace them with 10.9 grade bolts and if the bolt heads are hard to get a wrench on due to the curve of the bracket, I put an extra lock washer under the head of the bolt to get a better grip on it with the wrench.
  6. sourdiesel404

    sourdiesel404 Member

    and this method will stop my tensioner from moving?
  7. crassius

    crassius Well-Known Member

    other thing are involved in that also - the tensioner should be set to feed the chain straight onto the rear sprocket with teeth hitting dead center in the chain gaps - another thing is to be sure the chain is at its tightest spot before setting tensioner, try setting tensioner fairly loose, then roll bike a bit and see if chain gets tight and pushes tensioner down - when you can do this and see at least 1/2 inch of chain slack at every spot while rolling the bike, then tighten the sh*t out of the tensioner : )
    sourdiesel404 likes this.
  8. sourdiesel404

    sourdiesel404 Member

    now do I need to replace the old rubber mounts that sets the rear sprocket with new 1s? theyre bout 7 months old
  9. crassius

    crassius Well-Known Member

    those rubber rings usually last forever - when you replace the spokes just turn them over if the spokes have cut deep grooves in them so the spokes will be on the smooth side