Footpeg bolt failed while riding

[Wade Bartlett]

I guess I should clarify that the bottom was in tension initially, with 
the top (in the photo) in compression (this would have been on the 
bottom as installed in the bike).  As the fracture progressed, the 
tension region moved down with the leading edge of the fracture, and at 
the very end end, plastic deformation pulled the thread away at the top 
(of photo, which is the bottom as installed) - it probably has more of 
those little periperal radial cracks at the root of the next thread 
which weakened it somewhat, too.
HTH. -W

Patrick Mullen wrote:
>> The bolt was
>> in compression on the TOP and in tension at the BOTTOM,
> 
> I'm a little confused by this statement because the first photo, with
> the footpeg
> in view, makes it look like the part with the thread that sticks out was pulled
> apart from the bolt.  The extra thread is on the same side as the top of the
> footpeg if you were to straighten the hinge.
> 
> Unless I'm looking at it wrong, of course.