Stairmaster 8G Gauntlet Service Manual page 53

To correct this, use a 1/8" allen key to loosen the two (2) gearbox set screws, then pull the sprocket away from the body
of the gearbox until clearance is achieved. Be sure to tighten the set screws after spacing the sprocket.
If the unit is still experiencing the issue after spacing the sprocket away from the gearbox, check the following to ensure
there is no mechanical binding in the rest of the unit:
- Check to ensure all wires are secured away from the steps and chains.
- Check the alternator belt tightness, the belt should have 90 degrees of deflection.
- Check step chain tension to ensure step chains are not overtightened.
- Check the bolt that secures the idler arm to the gearbox is not overtightened.
If all of the above points have been checked, it's possible that the brake may be tensioned incorrectly and needs to be
realigned and tensioned. Please see Document
should be cleaned carefully if this issue continues.
#637-4306 "8-G Brake Assembly Alignment. " Specifically, the clutch plate
Page 53