Tire Diameter

[g zero]

Apparently all Good Year tires ( Flight Custom ) are not the same diameter.
I set my wheel pants close (for speed) … this is the third set ….1st set that ever touched the pant . Guess I have an extra rain groove . I set the pressure to 52 psi .

 

[RV8JD]

Bummer.

The GY tire specs for the Flight Custom III 5.00x5 tire (4, 6 and 10-ply-rating) shows a maximum inflated outside diameter of 14.2" and minimum inflated outside diameter of 13.65". Same for the Flight Special II. I don't think that takes into account any increase in diameter due to centrifugal force of the spinning tire.

 

[plehrke]

Spec should list a thrown and grown tire diameter. It takes into account spinning tire (thrown) and an increase due to age and wear (grown). Old tires actually grow in diameter, at equal inflation pressure. Weaker rubber, I guess.
Section 7 of the Goodyear catalog has a few formulas to calculate thrown and grown.
https://www.goodyearaviation.com/resources/pdf/Aviation-Databook-2022.pdf

 

[RWoodard]

52psi seems like a bunch. I could see how that could increase the diameter. I think most people are more in the 30psi +/- maybe 5psi for 5.00 x 5 tires.

 

[RV8JD]

Many folks with RV-8s (flat gear legs) run between 40 and 50 psi. I normally fill to 52 psi, and then refill before the tire gets down to 40 psi. The 5.00x5, 6 ply tires are rated for 50 psi.

 

[climberrn]

52psi seems like a bunch. I could see how that could increase the diameter. I think most people are more in the 30psi +/- maybe 5psi for 5.00 x 5 tires.

7A and 6A. I run 45 in the mains.

 

[DanH]

Minor note to builders...Tom has James pants, which are kinda flat-topped. Vans pants are more rounded at the top. Put the two uppermost nutplanes on each side of the center...none in the center of the thread.
.

 

[jliltd]

I have similar wheel pants on my RV-8 and use 55psi with Goodyear Flight Custom III's. The current set was dismounted from the wheels and remounted reversed on the rims and on opposite gear after the outboard treads wore down more than the inboard treads due to normal gear camber. I swapped gear sides so the rubber bias would still be running in the same forward direction. They have given another 180 hours since and I am getting close to changing them for a new set of Michelins I have on the shelf ready to go.