What makes R197 such a low rolling resistance tire?

Three key areas contribute to
low rolling resistance:
1. Casing
2. Tread design
3. Tread and sidewall compounding

If you’ve been following our series in Real Answers about tire-related fuel economy in large trucks, you know tread compounding and tread design contribute 35 to 50 percent to a tire’s rolling resistance. The other 50 to 65 percent is the result of the casing.

Before we go any further, what is rolling resistance?

There is always resistance between the tire and the road surface. Rolling resistance is a way to measure the energy you have to exert to roll a tire down the road. Just remember: The lower the better.

The R197 uses an advanced energy-efficient casing that controls and reduces flex. As you know, too much flex generates heat, which consumes energy and lowers fuel economy.

With the energy-efficient casing, you’ll save fuel even when it’s retreaded.

So fleets have a uniform look.

Exactly. Many fleets prefer to have a consistent appearance among new and retreaded tires. Frankly it often looks better. Especially if you’ve had to replace one set of tandems.

How does the compound promote fuel efficiency?

Bridgestone uses cap/base tread compounding.

This innovative tread compounding, along with special sidewall compounding, means lower rolling resistance and better fuel economy, because less fuel energy is wasted as heat.

How is the R197 for traction?

Both the R197 and B197 have excellent traction. Earlier we mentioned the classic five-rib design. What that does is provide more space in the grooves to allow water to escape from the footprint. For even better wet traction, the R197 and B197 use cross-rib sipes to improve wet traction by cutting through road films.

And those smaller sipes on the rib edges?

The small notches perpendicular to the ribs are stress-relief sipes. They’re there for longer, smoother wear. Which is a big part of the story, especially for the R197. And that is how you can save fuel and still enjoy traction, retreadability and impressive mileage.

While the R197 is Bridgestone’s lowest rolling resistance tire ever, tests are showing the trailer radial is offering long, even wear.

Editor’s note: For more on how the Defense Groove structure works, see the article “technically speaking” in the last issue of Real Answers,
Volume 15, Issue 2, page 18.

What’s the result?

It “sacrifices” itself so irregular wear doesn’t spread to the main ribs.

Another feature that protects the R197 from irregular wear is the shallow
11/32" tread depth.

What about the B197?

It has the same shallow 11/32" tread depth. While we’re looking at the R197 and B197 treads, take a look at the ribs. They seem like ordinary ribs, but actually they’re a bit wider than usual. More tread volume means more rubber in contact with the road surface for longer mileage.

Four steel belts and a tough steel body ply enhance durability while thick ribs on both sidewalls fight curbing to protect the casing.

When are they available?

The R197 is available in the 295/75R22.5 low profile size. More sizes should be available soon. The tread width range for B197 will accommodate many popular casing sizes.

For more information, contact your dealer or BCS representative. For a free brochure, call 1-888-694-0469. Ask for item #TEO6530792. You can also request a brochure by visiting www.BridgestoneTrucktires.com.

Does your fleet carry this sticker?

Then you know SmartWay is an innovative, voluntary partnership of the EPA that reduces greenhouse gases and improves fuel efficiency. The Bridgestone R197 is approved for use on SmartWay-designated trailers.

Headed to California?

The Bridgestone R197 complies with California’s  rules mandating SmartWay-verified low rolling resistance tires on trailers 53 feet and longer. And when it’s time to retread, a Bandag B197 tread on an energy-efficient R197 casing is CARB-compliant.