Tire help

[kendive]

All I can say is good luck Kendive.

Because now I have to give an update.

I finally got a little free time so I decided to go through the trouble of measuring the ACTUAL rolling circumference of the Carlisle All Trail vs the Firestone Turf & Field. Luckily, I mount my own tires using a manual tire changer so I was able to do this experiment at no cost other than a sore back (hey, I'm 54 years old, cut me some slack) and some time.

First I checked the air pressure in the Carlisle I had already mounted. 28 psi is where I run these tires on the tractor. Used a level to put a mark at the top and bottom of the tire (vertically level) then a mark on the concrete at the bottom of the level. Rolled the tractor forward till the marks went one full revolution and came to vertically level again, then put a mark on the concrete. Measured the distance between marks (which is of course the rolling circumference). The Carlisle have a loaded (please note I have a FEL installed) rolling circumference of 60 inches.

I removed one of the wheels, dis-mounted the Carlisle, mounted the old OEM Firestone I had recently taken off. Put the wheel back on the tractor with 25 psi in the tire. Used the level to duplicate the way I made the marks again. Measured between the marks and found out the Firestones have a loaded rolling circumference of 62 inches.

Now I'm a little surprised at the Firestones because the Firestone website specifies a rolling circumference of 61 inches. This means we can't even go by the info provided by the tire manufacturer.

Now I have to eat my words because I decided that was too much difference. I took the other Carlisle off and I'm back to running the dry rotted Firestones for now. Looks like I may be back to square one of getting all four wheels and tires replaced with R1s. This doesn't really bother me too much because I could use the extra traction anyway. But for those of you that need turfs, I can't recommend the Carlisle All Trail like I originally thought (unless you never use 4X4).

Good info here what I found out from Kubota and the dealer.

http://www.tractorbynet.com/forums/kubota-owning-operating/173835-those-looking-20-5x8-10-a.html

 

[jonbt]

I just mounted a pair of the Carlisle All Trail II in 22x9.5-10 on my Kubota B1750 4x4 to replace the Bridgestone 20.5x8.0-10 turf style tires which had little tread left and were getting side wall cracks. The B7100 and others also use the 20x5x8-10s. I spent a lot of time looking and following the various threads here before deciding. I felt that the All Trail 20x10.0-10s would be too small, since other posts have pointed out that it is better to run a 4x4 in a lead condition (front tires slightly larger than stock) rather than a lag condition (front tires slightly smaller than stock).

I'm very happy with the results. There are no issues with sidewall clearance on my B1750 (although there may be on other tractors -- you just need to do a visual). The 22x9.5-10s are slightly taller (0.5-1"), but no wider than the 20.5x8-10s they replaced when inflated to their maximum 14 psi recommended pressure. They have a rounded shoulder profile rather than the square profile of the Bridgestones, and of course a much more aggressive tread, which is what I wanted for the 4x4. My rear tires are 31x15.5-15 z-bar style (not turf, not ag, not R4s, don't know what else to call them) with a tread pattern similar to the All Trail II's.

Note that the 22x9.50-10s have a maximum load of 585 lbs each, so you probably should NOT use these with a front end loader. My B1750 is fitted with a front hydraulic plow blade, so this load range will work just fine. I think you could put a snowblower or broom on the front too, just not an FEL.

I want to point out that the rolling circumference, NOT the loaded diameter, is the most important factor when trying to match the front/rear tires on a 4x4. Over- or under-inflating to change the apparent diameter does not make a difference. Think about the limiting case of a bulldozer tread: every inch of it has to contact the ground to complete one rotation, and it does not matter whether that bulldozer tread is elliptical as it normally is, or round like a tire. You can reduce the tire pressure until it looks flat, but every inch of it still has to contact the ground to complete a rotation, right? All you do with the inflation pressure is change the size of the footprint.

My 2 cents and a little more!