Pro-Form HYBRID TRAINER PFEL03721C.0 User Manual page 26

HOW TO ADJUST THE DRIVE BELT
If you can feel the pedals slip while you are pedaling,
even when the resistance is adjusted to the highest
level, the drive belt may need to be adjusted.
To adjust the drive belt, first unplug the power
adapter. Next, remove the M4 x 16mm Screw (84)
from the Side Access Cover (21), and then remove the
Side Access Cover by moving it in the direction shown
by the arrow.
21
84
Loosen the M10 x 55mm Shoulder Bolt (99). Then,
tighten the M8 Locknut (68) until the Drive Belt (64) is
tight.
99
When the Drive Belt (64) is tight, tighten the
M10 x 55mm Shoulder Bolt (99). Then, reattach the
side access cover and plug in the power adapter.
26
68
64