How to Prevent Motor-Grader Lope

September 28, 2010

If your graders lope, or bounce, you may be able to improve the productivity and accuracy of finish work by adjusting weight distribution. Most graders are designed to carry 33 percent of their weight on the front tires. Bridgestone's field testing shows that in the worst case, weight distribution should never shift beyond 30 percent front and 70 percent rear.

If you've installed an attachment—such as a ripper, scarifier, push block, or roll-over protector—you may need to check and adjust weight distribution to match the original-equipment design. Bridgestone testing also suggests that the best ride and minimum bounce occur when the tires' cold inflation pressures match specifications for the actual load on the each tire. In some unusual cases, this means tires on one grader may need different inflation pressures.

Typical Grader Application*

Front tires**  Rear tires** 
Weight distribution 0.33 × 32,000 lbs. = 10,560 lbs.  0.67 × 32,000 lbs. = 21,440 lbs. 
Tire load 10,560 lbs./2 = 5,280 lbs. 21,440 lbs./4 = 5,360 lbs.
Tire pressure 24 psi 25 psi
Grader GVW: 32,000 lbs; Distribution: 33% front axle, 67% rear axle**14.00 - 24 bias ply