Conti mpt 81 questions

[milo12]

Trying to figure out what tires I want for my project. The MPT 81's seem to fit the bill. First question; Do you need beadlocks or special rim shape to use these at low (20 psi) pressures? I will be putting these on a Dodge 5500 so i will need custom 10 lug wheels with custom back spacing. Second question; I looked at the Conti tech data and i'm confused by the sizing data. it says the 275 has a 440 mm radius. This converts to a 34.6 inch diameter. But the 275/80-20 designation calcs out to a 37.2 in diameter, which is right?

Any comments on personal experience with these tires would be appreciated.

 

[Robthebrit]

I use them on my mogs but I only use 335r20/80 (40 inches) and 360r20/80 (44 inches), both of them mount to an 11x20 rim. As far as I remember they have a standard tubless beads. They are really quiet, they wear well and are track really straight. They are not great in think goopy mud but they are good in more firm dirt, rocks, sand and snow. Speed limit is a little low at about 55-60mph but I drive a mog so 60mph is all I need. They take a lot of abuse and I have aired mine down to 12-15psi on the 416 doka, and never pulled one of the bead and the empty truck is about 9000 pounds. I have heard of people debeading them in deep sand with heavy side loads, such as what happens when you slip sideways down a sand dune.

If you have any specific questions PM me.


Rob