So how much bigger will farm tires get? Last month Michelin introduced what it claims is the largest tractor tire in the world. The Michelin AxioBib IF900/65R46 is a Group 50 tire that measures 900 mm wide (2.5 ft.) and 2.32 meters tall (7.6 ft.). The tire can carry loads up to 10,600 kilos (22,000 lbs.) and run at speeds of 65 km/hr (40 mph). It is designed for 4-wd tractors rated 350-plus hp. It also fits combines and forage harvesters.

The company says this taller, larger-diameter tire provides 12% to 15% better traction than the next size down, a 15% longer footprint, and increased fuel savings due to the length of the tread, which makes movement more efficient. The tire features Michelin’s Ultraflex technology, which allows it to carry heavier loads at lower inflation pressures.

The tire was showcased on a New Holland T9 4-wd tractor at the global farm show Agritechnica. Earlier in the year, at the Farm Progress Show in Decatur, Ill., Michelin displayed a prototype of the tire in a smaller version.

Currently the tire is available only in Europe to meet road-width constraints of 3 meters (10 ft.). The U.S. also is being considered as a potential market. Further commercializing will depend on the companies who make the equipment, says Emmanuel Ladent, president of Michelin’s strategic business unit for agricultural tires. “The technology exists,” Ladent says. “It is available in our showrooms now.”

Ladent says an even bigger tire is in the works to further increase traction and load-carrying capacity. “Now, we already are working on the tire of tomorrow.”

How to read a farm tire

Here is what the numbers and letters on the side of a tire mean.

>EXAMPLE: 500/70R24 

500: width of the tread in mm

70: sidewall aspect ratio, or the ratio of sidewall height to tire width at the tread (indicating that the sidewall height is 70% of the tread width)

R: radial tire (vs. bias ply)

24: rim diameter in inches