Just be careful screwing those tires onto the rims that you don't screw them into the tubes

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The other problem with the Goodyears is that the sidewalls just arent' very flexible. So, you get down to a certain pressure--about 10 or 12 pounds, and the issue is no longer inflation pressure, but sidewall stiffness.
They are fine tires for 99% of what MOST folks do with little airplanes. For the rest, Bush Wheels are the deal.
I can tell you, however, that I've met guys in some pretty ugly places with Cubs on 8.50 X 6.00 tires. It's just that one "oops" that makes big tires worthwhile.
MTV