Operation Manual

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PART II
Fatigue Is Not A Perfectly
Predictable Science
Fatigue is not a perfectly predictable science, but
we can give you some general factors to help you
determine how often you need to inspect (or have
your retailer inspect) your bicycle. The more you t
the “shorten product life” prole, the more frequent
your need to inspect. The more you t the “lengthen
product life” prole, the less frequent your need to
inspect.
Factors that shorten product life:
• Hard, harsh riding style
• "Hits," crashes, jumps, other "shots" to
bike
• High mileage
• Higher body weight
• Stronger, more t, more aggressive rider
• Corrosive environment (wet, salt air,
winter road salt, accumulated sweat)
• Presence of abrasive mud, dirt, sand, soil
in riding environment
Factors that lengthen product life:
• Smooth, uid riding style
• No "hits," crashes, jumps, other "shots"
to bike
• Low mileage
• Lower body weight
• Less aggressive rider
• Non-corrosive environment (dry, salt-free
air)
• Clean riding environment
Aluminum Frame Inspection
1. Clean the bike and remove the wheels.
2. Inspect the whole frame carefully for cracks.
Pay particular attention to the underside of the
downtube where it intersects the headtube
3. Next carefully inspect the area where the crankset
and rear wheel come closest to the right chainstay,
particularly on the innermost part of the
chainstay and the outermost part of the chainstay.
Next look at the welds that join all of the tubes.
Be sure to look at the inside of the rear triangle
or swingarm while the wheel is out, including the
dropouts.
4. Finally check all mounting points such as disc
brake caliper brackets and water bottle and rack
mounts.
Figure 21.
TOPTUBE
DOWNTUBE
HEADTUBE
Inspect this area for cracking