I would be interested in gathering data to put into some sort of spread sheet that lists different tires "loaded radius" or the distance between the ground and the axle center. I think there are so many variables out there in tire sizes. Example...I had a set of 25" Dirt Devils on my P400 and they were at least 2 inches shorter (diameter) than the 25" Goodyears on a friends Polaris 600. I need to put new skins on my P650 and was leaning towards the 26" Dirt Devils, but I saw a post where the 25" radial Maxxis Bighorns were taller. Since what I'm mainly interested in is ground clearance, the "loaded radius" should be helpful to decide which tires to buy. If everyone will submit their front and rear tires sizes along with an ACCURATE measure of the distance from the ground to the axle centerline, I'll organize them and make them available to everyone. Also, I'm going to pull tire weights off different websites and add that to the database. If you have an accurate scale, and know the weight of your tires, post that too.

To keep the variables to a minimum and the measurements consistent, let's do the following:

1. Measure using a square from the concrete to the axle (rear) itself behind the tire. The distance to where the square touches the axle should give you a pretty accurage measurement. On the front it will be easy to misalign so try to be precise to the center of the hub.

2. Measure with no one on the ATV itself.

3. How 'bout we air up to 6 lbs.? Seems most guys run from 5-7 lbs., so 6 will hopefully be a happy medium. I know different ATV weights and air pressures will affect our measurements, but hopefully we'll be able to get some idea.

4. Let's try to keep the data base for new tire measurements. If your tires are worn 1/4", then add that to your measurement.

Post the following info:

Tire size, make and model... loaded radius measurement...make and model of ATV it was measured on and ATV weight if you know it...and an accurate tire only weight if you know it.

Give me a few days to create the database and a link.

Thanks in advance!

Larry

 

'02 Prairie 650 (approx. 600 lbs.)

stock tires @ 6 psi

Front:
Dunlop KT121A 25X8-12 11.75"

Rear:
Dunlop KT127A 25X10-12 12.25"

Going from 5 psi to 7psi on the rears increased "loaded radius" by 5/16".

 

Sorry guys, but guess i should have put this in the suspension, drivetrain and tires forum. Anyone know how I can move this over there?