Can BIAS Tires Beat Radials?

by | Dec 1, 2018 | Featured, Tire Technology | 0 comments



Can old school 1930’s Bias Ply Technology provide better traction than latest High Tech Radial?

The short answer is YES!

I don’t believe it, you say.  Surely these high tech radials must always out-pull Dad’s Old Bias tires, right?

The answer depends on your tire pressure!

When your New Radial’s air pressure is matched to the axle load, they will always out-pull their Bias counterpart. But if the Radial is over inflated, the Bias tire with the correct air pressure will probably win.

The sad truth is many farmers over inflate their tires for various reasons:

  • Tire Looks Low.
  • The Tire Changer Erred on the Safe Side:  tires were set at 25 psi and may only need 12 psi.
  • Tires were Inflated for a Heavy 3 or 2 Point Implement or Planter, then not deflated for a disk or pull type ripper.

OK, sounds reasonable, but has anyone ever tested Bias vs. Radial head to head?

Yes!  In my career at a major agricultural tire manufacturer, we tested a new Bias vs new Radial with the exact same tread pattern to confirm.

The tractor was a 4WD hooked to a load unit that measured pull and slip in real field conditions.


Correct inflation was 12 psi for both tires.

The results were what you would expect.  With both tires at 12 psi, the Radial out-pulled the Bias by 7 to 9%.

We then over-inflated the radials to a typical field pressure of 20 psi.

The 12 psi BIAS tire BEAT the 20 psi RADIAL!

What does this test mean for you and your tractor?

If you are running over-inflated radials, you are probably:

  1. Burning More FUEL
  2. Seeing More TIRE SLIP
  3. Creating More SOIL COMPACTION that can reduce yields.
  4. Creating Deeper RUTS in soft fields.

My advice, contact your local tire dealer to properly set your tire pressures, unleashing all of the benefits your new new age high tech radial AG Tires can provide.

When you do, your wheel tractor will probably give the track tractor a run for its money!

All information is provided in this blog solely to provoke thought. All deductions made from information on this site must be confirmed by Certified Ag Tire Dealer before use. Ag Tire Talk does not recommend anyone conduct tire service work with exception of Certified Ag Tire Dealer Professionals.

Ken Brodbeck is an Ag Engineer who spent 35 years at a major ag tire manufacturer. He is now Co-Owner of Precision Inflation, LLC, an Independent Dealer for German PTG Inflation Systems for Agricultural Machinery.