My gear sprocket spins freely.

Discussion in 'Transmission / Drivetrain' started by Ty the motor guy, Jun 12, 2016.

  1. Ty the motor guy

    Ty the motor guy New Member

    help, at first when I turned corners, my bike would rev high and not move. I shut it off started back up. And the week spinner when the clutch was engaged, thought it was clutch pads, put new ones in. Tried it and still the same, looked at the gear sprocket, and the nut in the middle was lose, I took it off and tried installing it again, it can't get tighter cause the motor turns over, and the sprocket spins both ways freely like you would put a piece of round metal circle on a pencil and spun it.

  2. Frankfort MB's

    Frankfort MB's Well-Known Member

    You need to be pulling the clutch handle while your tightening the nut
  3. crassius

    crassius Well-Known Member

    you've lost the woodruff key that locks the sprocket in place
    gary55 and FurryOnTheInside like this.
  4. Frankfort MB's

    Frankfort MB's Well-Known Member

  5. agrmodz

    agrmodz Member

    This has happened to my friends bike and how do i find out if its the woodruff key? like u can pull the clutch in and it will roll or you can let it out and it will roll
  6. crassius

    crassius Well-Known Member

    open both covers and look while rolling bike - if drive sprocket turns and the nut on it doesn't turn, that is the bad key - look on other side to see if nut turns, but clutch hub doesn't for bad key on that side
  7. KCvale

    KCvale Motorized Bicycle Vendor

    Just stick a socket wrench extension in the plug hole to keep your piston from moving when tightening the small gear, but first you'll need a new woodruff key to keep the gear from spinning on the shaft.