This is one of the most common problems on NordicTrack machines. If the spool on your arm exerciser always has the knob backing off, you have a simple fix?replace the thrust bearing assembly in the spool assembly. It is a cheap fix for $9.95 and we have the parts.
The bearing allows the assembly to apply force against the leather friction pad without causing the knob to turn with the direction of the force and once the bearing wears out, you simply have to replace the bearing assy.
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