3 things, depending on the machine, the roller under the case sometimes has screws fixing and when the work loose (falling off) the plastic wheel attached to the roller slips.
2nd, tighten the rollers at the back so the belt is taught but not too tight
3rd, oil the tread, it helps with the grip on the roller kinda lubrication adds like a little suction to the process
www.4af.co.uk great for repairs
Troy
November 2009
Automatic Answer
We may have found other answers which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix gym/fitness equipment.