What's the best way to measure for tire size.

Most of the time it's guess work and head scratching or copy cat what others are currently running.

I've always been interested in one of these Percys tire measuring tool.
Just wondering how accurate they are.

I've mentioned this in earlier posts, I made my own gadget based on the Percy's tool. It wasn't too hard to do, and the bottom line is it worked perfectly and when my wheels / tires showed up they fit exactly as I expected they would. Just made another one for my son last weekend, as he is looking for new wheels/tires for his Suzuki Sidekick hunting wagon project. Takes out ALL the guesswork.
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