Footpeg bolt failed while riding

[Jim Stewart]

Wade Bartlett wrote:

> I disagree. The fracture face shows absolutely no metallurgical problems 
> (granted something might turn up with an SEM or even a decent optical 
> microscope, but given the photo we have to work with now, there's 
> nothing visible).  Multiple minor fractures around the periphery suggest 
> an initial overtorque, the beach marks" across the face indicate that 
> the overtorque was followed by fatigue, which progressed in a modest 
> number of steps (I can count at least 18 fracture progressions in that 
> photo). The final fracture was at the angled part near the top of the 
> fracture photo.

Wade - can you expand on your comments? I guess I see the fracture progressions 
at the thread root. How about the almost horizontal striations through the core 
of the bolt?

Any further clues that appear to the experienced eye?

Thanks...

-js


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