Flexion tire technology offers improved performance and cost of operation
04/30/2014
John Deere Tractor
Flexion tire technology offers improved performance and cost of operation
Tires are quite literally where the rubber meets the road for tractor performance. Proper tire selection and air pressure can be the difference between a high-performing tractor and an underperforming one.
How are increased flexion (IF) and very high flexion (VF) tires different than standard technology radial tires?
IF tires
20 percent less air pressure to carry the same load as a standard radial tire
20 percent greater load capacity than standard radial tires inflated to the same pressure
VF tires
40 percent less air pressure to carry the same load as a standard radial tire
40 percent greater load capacity than standard radial tires inflated to the same pressure
Figure 1 shows the resulting footprint of three different tires under the same axle load: an overinflated standard 480/80R50, a properly inflated standard 480/80R50, and a properly inflated IF480/80R50.
Figure 1 - Air pressure impact on tire footprint
Tire
Standard
480/80R50
Optimized standard
480/80R50
Optimized IF
480/80R50
Axle load
21,500 lb
Inflation
30 psi
(2.07 bar)
16 psi
(1.10 bar)
12 psi
(0.83 kPa)
Footprint
24 x 15.5 in.
(610 x 394 mm)
30 x 16 in.
(762 x 406 mm)
35 x 18 in.
(889 x 457 mm)
Approximate area
372 in.2
(2400 cm2)
480 in.2
(3097 cm2)
630 in.2
(4065 mm2)
Area increase
Baseline
29 percent over baseline
69 percent over baseline
* Demonstration and data were completed at the 2012 National Tractor Sales Training Program
What benefits does running at a lower air pressure provide to customers?
Tires with lower air pressure have a larger footprint, meaning that their load is distributed over a larger area (see Figure 1). Benefits of this include, but are not limited to:
Performance - improved traction
Performance - reduced tire slip
Performance - better ride quality
Performance - reduced compaction
Cost of operation - improved total fluid economy
A tire footprint increases in both length and width with reduced air pressure. The width increase can be attributed to the increased bulge at the base of the tire making contact with the ground, or what is commonly referred to as the cheek of a tire. A properly inflated IF or VF tire will have more cheek than a properly inflated radial tire when carrying the same load. Always consult the operator's manual to determine the appropriate tire pressure based on your tire selection and axle load.
Application specific examples
Table 1 - 9560R with 800/70R38 duals
Radial solution
IF solution
Reduction in pressure
Front
11 psi
(0.76 bar)
8 psi
(0.55 bar)
27 percent
Rear
7 psi
(0.48 bar)
6 psi
(0.41 bar)
14 percent
*Air pressures are comparing Michelin radial and IF solutions and tire ratings
Table 2 - 8R configured for 1770NT 24 row planter transport load
Radial solution
VF solution
Reduction in pressure
Dual 420/85R34 (front tires)
18 psi
(1.24 bar)
10 psi
(0.69 bar)
44 percent
Dual 480/80R50 (rear tires)
24 psi
(1.65 bar)
14 psi
(0.97 bar)
41 percent
*Air pressures are comparing Michelin radial and VF solutions and tire ratings
