LifeSpan Jazz Owner's Manual page 28

NOTE: When properly tightened, you should be able to peel the very edge of the side of the belt up
approximately 2 inches. However this is a rough reference and not all treadmills are the same. Some treadmills
that have longer belts may give different measurements for correct belt tightness.
Simply, if the belt begins to slip during use, this is an indication that the belt still needs tightening.
Video Tutorial Available at:
http://youtu.be/vllsamTSvvA
JAZZ
Lifespan Fitness Channel:
http://www.youtube.com/user/treadmillsvideos
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