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Old 11-09-2012, 03:05 PM
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csmeance csmeance is offline
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There are a few things going on here that are causing it. Weight limit is one of them.

Basically a tire is meant to ride on it's treaded surface and sometimes a little bit on it's side, IE Camber (to an extent). Typically 1-1.8 degrees of camber is perfectly fine. However go past this and tires can fail pretty badly since the sidewalls aren't designed for that specific duty.

EDIT: Also stretching a tire on a rim it's not designed for can also put a LOT of pressure on the sidewall and the cords that hold the tire together, which it looks like in the first picture!

You said you keep your tires around 40 PSI, this over inflates the center of the tire putting a slight bulge in it. The steel cords have to work harder to make sure the tire stays within it's shape. As well with 40 PSI the pressure can vary a bit, I wouldn't be surprised that the tires get up to 45 PSI when warmed up! This large change in pressure plus the high pressure is putting a large strain on the cord, and as well the rubber surrounding it.

Heavy weight is a huge killer of tires. Remember they are rated to only handle a certain load per tire, and that's under optimal conditions! In this case the OP had a tire with cords that were straining already, and then may have exceeded the weight limit putting even more of a strain on the cords and the surrounding rubber.

Add some driving into the mix and then what you have is the rubber separating from the stressed cord, and then appearing like what the OP posted. Over time this can get worse with the tread/sidewall separating or a blowout!

Last edited by csmeance; 11-09-2012 at 03:35 PM.
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