Fatigue Is Not A Perfectly Predictable Science; Factors That Shorten Product Life - Flash FLASHV1 User Manual

SIMPLE RULE 3 : Inspect and investigate any staining to
see if it is associated with a crack.
• SIGNIFICANT SCRATCHES, GOUGES, DENTS OR
SCORING CREATE STARTING POINTS FOR CRACKS.
Think about the cut surface as a focal point for
stress (in fact engineers call such areas "stress ris-
ers," areas where the stress is increased). Perhaps
you have seen glass cut? Recall how the glass
was scored and then broke on the scored line.
SIMPLE RULE 4 : Do not scratch, gouge or score any
surface. If you do, pay frequent
• SOME CRACKS (particularly larger ones) MAY
MAKECREAKING NOISE AS YOU RIDE. Think
about such a noise as a serious warning sig-
nal. Note that a wellmaintained bicycle will be
very quiet and free of creaks and squeaks.
SIMPLE RULE 5 : Investigate and find the source of any
noise. It may not a be a crack, but whatever is causing
the noise should be fixed promptly.
In most cases a fatigue crack is not a defect. It is a sign that
the part has been worn out, a sign the part has reached the
end of its useful life. When your car tires wear down to the
point that the tread bars are contacting the road, those tires
are not defective. Those tires are worn out and the tread bar
says "time for replacement." When a metal part shows a
fatigue crack, it is worn out. The crack says "time for replace
ment."

Fatigue Is Not A Perfectly Predictable Science

Fatigue is not a perfectly predictable science, but here a
re some general factors to help you and your dealer deter
mine how often your bicycle should be inspected. The
more you fit the "shorten product life" profile, the more
frequent your need to inspect. The more you fit the "length
en product life" profile, the less frequent your need to in
spect.

Factors that shorten product life:

• Hard, harsh riding style
• "Hits", crashes, jumps, other "shots" to the bike
• High mileage
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