Carbon wheel broke



fujimo

New Member
Dec 15, 2002
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I bought a used carbon wheel and upon arival the wheel was out of true and warped in one spot of the rim. After my first ride, a 20 mile time trial on good pavement, the wheel bulged and cracked where the rim was warped. Does the following excerpts from Zipp's technical info imply that it was damaged upon arrival or from my my 20 mile time trial (I weigh 140lbs)?

" the fault may be a big rock coming in contact with the downtube. While the tube might not fail from such a large impact, the repercussions are usually hidden on the inside of the laminate, or within the laminate. Microcracks can then spread through the matrix, decreasing the ability of the fiber to transfer load"

"we're dealing with a material that doesn't have an overabundance of ductility. Composite designs are not meant to permanently bend. And when they fail, they fail all at once, so designers build in a big safety net."

Thank you, Shawn


http://www.angelfire.com/blog/cipoman/DSCN4966s.JPG

http://www.angelfire.com/blog/cipoman/DSCN4971s.JPG