On a tractor-trailer driver site I found this tip to help determine how many miles you'll get from your tires: measure them.
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That is - my new Elite III's, according to Dunlop have only 12/64" tread depth on the front at the recommended pressure- 40psi. I believe that most states say that when they get down to 4/64" or 6/64" (depending on the state you're in) they're at the legal replacement point.
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Ok, measure them yearly, or say after every 5K miles. If at the 5K point, you measure 9/64" remaining, you've used 3/64" or 1/2 of the total usable tread. (12/64"(front) minus the legal limit, 6/64", giving only 6/64" usable tread depth). You will probably get 10,000 miles on that tire - unless you change the way you drive, the air pressure, or the roads you're on. Hot and/or rocky ones eat the tread faster I'm told; on the other hand, higher tire pressure may keep tires cooler, but reduces contact patch/ grip.
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Even if you don't know how much tread depth you had originally or didn't record the miles on the bike when you installed them, you can still use this tip to track how fast the rubber is wearing off. Oh, and I used 64th" of an inch as it's easier to do the math.
But - check the math to be sure I quoted it o.k. - I've been prone to typos lately. (and wrong turns
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