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Old 06-11-2010, 02:49 PM   #46 (permalink)
CapriRacer
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Quote:
Originally Posted by AeroModder View Post
Some are inward, but there are a few outward ones:

http://i3.photobucket.com/albums/y93...ey/tire005.jpg

http://i3.photobucket.com/albums/y93...ey/tire006.jpg

After reading the link, these are definitely defective. The cords are very poorly lined.
As a generic term, these are called "undulations". They are caused by uneven spacing of the ply cords.

"Bulges" are wider than normal spacing - and the one in your photo is not too bad. Nothing to worry about.

"Indentations" are caused where the ply fabric overlaps during the manufacturing process. The tire is actually stronger there. You will always find one for every sidewall ply listed on the tire (perhaps 2!) In your photo, those are fairly normal. Nothing to worry about.

BTW Nitrogen behaves very much like air and increases pressure with increasing temperature just like air. In fact, there is very little advantage to using nitrogen:

Barry's Tire Tech
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