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Tire Expert Center

May 17, 2018

What is a Cyclical Field Operation Tire, when should grower choose “CFO”, and what yield and productivity benefits can grower expect to receive? 


Before the introduction of IF and VF marked radial tire, bias and standard radial tires had been used on equipment with cyclic loading conditions, but the tires didn’t require any extra identification. The standard developed by The Tire and Rim Association approved cyclic loads with + 6 PSI for Field Service Maximum Cyclic Load. The standards allowed extra loading on bias and standard radial tires based on the application and travel speed of the equipment.


When the tire industry introduced the IF and VF marked radial tires, the standards did not allow extra loading based on reduced speed or application. When farmers started to see the benefits of the IF and VF tires on their tractors, they requested to use the IF and VF marked radial tires on their combines and grain carts. To address the requests, the tire industry introduced the CFO standard for the IF and VF marked radial tires. An IF/CFO marked radial tire will still carry 20% more load than a standard radial tire for road transport, but in cyclic service, it will carry an additional 55% more load without increasing the inflation pressure. For farmers concerned about soil compaction during harvest, the higher load capacities of the IF/CFO tires require less inflation pressure. To make this easier to visualize, Chart 1 shows the inflation pressure required for a flotation tire used on a combine. The chart compares similarly sized bias, standard radial and IF/CFO radial tires. The axle load for each class of combine is an approximate maximum cyclic weight for the machine. This is just a general comparison. Please consult your operator’s manual for axle loads to determine the inflation pressure required on your combine.


Chart 1: Tire inflation pressure (psi) based on cyclic axle load (lbs).


In the chart, a class 8 combine has a cyclic axle weight of 60,000 lbs. To be able to carry the load, a 76x50.00-32 bias tire requires 36 psi, a 1250/50R32 standard radial requires 28 psi, and the IF 1250/50R32 CFO radial requires 19 psi. If a farmer is trying to limit ground compaction, they would want the IF/CFO tire on the combine. 


The major benefit of using CFO tires on harvest and seeding equipment is being able to carry the axle load at lower inflation pressures compared to the same sized standard radial or bias. The lower inflation pressure helps reduce soil compaction in wet conditions. The IF/CFO tires will also have a larger footprint vs a standard radial, helping increase flotation during a wet harvest. On larger grain carts, the IF/CFO tires may have enough load capacity, allowing customers to still use one axle instead of multiple axles or tracks and control equipment costs. The CFO marked tires are just another tool customers have to help minimize soil compaction as the equipment gets larger.  


About Bridgestone Americas, Inc.:


Nashville, Tennessee-based Bridgestone Americas, Inc. (BSAM) is the U.S. subsidiary of Bridgestone Corporation, the world’s largest tire and rubber company. BSAM and its subsidiaries develop, manufacture and market a wide range of Bridgestone, Firestone and associate brand tires to address the needs of a broad range of customers, including consumers, automotive and commercial vehicle original equipment manufacturers, and those in the agricultural, forestry and mining industries. The companies are also engaged in retreading operations throughout the Western Hemisphere and produce air springs, roofing materials, and industrial fibres and textiles. The BSAM family of companies also operates the world’s largest chain of automotive tire and service centres. Guided by its One Team, One Planet message, the company is dedicated to achieving a positive environmental impact in all of the communities it calls home.


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