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It has pretty much always been true that the shorter the haul, the shorter the steer tire life. That’s because a larger proportion of the tire’s usage is in turning and maneuvering.

Fleets involved in regional or urban hauling, and especially P&D, know that scrubbing burns up steer tires quickly. Deeper treads sometimes help, but often bring with them the curse of irregular wear.

The fact is, short haul and P&D fleets need steer tires specially designed for their use. That’s what Bridgestone’s new R260F is, as we’ll see.

What makes short-haul tires wear out so fast?

Mostly, it’s scrub. When you turn, they scrub against the pavement. That’s like dragging an eraser across sandpaper.

The more turning and maneuvering you do, the more you grind away that tread.

At 22/32" the new Bridgestone R260F
is more than 20 percent deeper than conventional steer radials.

So what’s the answer?

One solution is a deeper tread. Most steer radials are about 18/32" deep. Generally, adding tread lengthens wear.

Why don’t steer tires have deeper treads?

The problem that can accompany deeper treads is irregular wear. For years, 18/32" has seemed to balance long tread life and low irregular wear.

What kinds of irregular wear?

Generally, it starts along rib edges and then spreads.

Because steer tires have to be removed, by law, when any part of the tread is at 4/32" or less, irregular wear can be a major cause of premature tire removal.

Is there a solution? Make a steer tire with a deeper tread, and figure out a way to reduce or prevent irregular wear.

Like the new Bridgestone R260F. It combines a 22/32" tread, more than 20 percent deeper than conventional steer radials, with irregular wear-fighting features to help you get even wear.

Bridgestone’s patented Equalizer Rib design
fights irregular wear using tiny ribs that sacrifice
themselves by wearing much more quickly than
the main ribs beside them.

How does the R260F fight irregular wear?

Notice the narrow ribs alongside the two main ribs. These are called Equalizer Rib™ structures – a patented, Bridgestone-exclusive innovation to fight irregular wear.

How do they work?

These tiny ribs are just a bit shorter than the others, so they are like the smaller tire in a mismatched dual pair. They wear faster than the main ribs beside them, just as the smaller tire in a mismatched dual pair does.

In doing so, they attract irregular wear forces that otherwise would attack the main ribs. In a sense, they sacrifice themselves to protect the main ribs.

The R260F’s Equalizer Rib design effectively channels irregular wear-producing forces away from the main ribs and into these small ribs, combating irregular wear.

Isn’t this what happens with your Defense Groove™ design?

Similar, but unlike Defense Groove tires, these ribs are located away from the shoulders. Still, what works for shoulders seems to work on inner ribs too.

Does the R260F also use the Defense Groove feature?

In short hauls or P&D service, that structure usually isn’t necessary. High scrub seems to “rub out” shoulder wear before it can become a problem. And, when tires are constantly turning and maneuvering, there’s a tendency for that outer rib to be damaged or torn, causing more severe wear problems.

Does the R260F have other features to combat irregular wear?

In addition to the Equalizer Rib structures, notice the tiny notches along the rib edges.

Tiny notches, called “stress relief siping,”
reduce squirm and scrub that can initiate rib edge irregular wear.

What do they do? A tire is round, except in its footprint. There, the round shape is flattened.

That causes stress and scrubbing along rib edges. This almost microscopic scrub can be a seed of irregular wear.

Notches in the rib edge allow it to be flattened with reduced edge stress. Called “stress relief siping,” these notches are very effective against irregular wear.

How is the R260F’s retreadability?

Like all Bridgestone radials, the R260F is designed to be retreaded. And a few special features make it a good retreading candidate.

Notice the shape of the Equalizer Rib structures and those little “buttons” at the bottom of the inside grooves? Both are designed to prevent stones from being captured.

The sloped shape of the Equalizer Rib
structures in the R260F help prevent damaging
stones from being captured and retained.

Why is that?

As a tire wears, retained stones are pushed into the tread. Eventually, they can drill into the belts, damaging them and allowing water and air to get in and cause rust.

Both belt damage and rust reduce retreadability.

Tiny platforms at the bottom of the R260F’s inner
grooveshelp prevent stone drilling that can damage belts
and cause them to rust, reducing retreadability.

Anything else?

The R260F, like any Bridgestone with the letter “F” in its model name, has thick sidewall protector ribs.

These ribs shield sidewalls from cuts and abrasion, prolonging useful life. And, because both sidewalls are ribbed, if one set gets worn away, you can flip the tire over for continued protection.

Sturdy ribs on both
sidewalls help protect R260F
casings from curbing damage.

When will the R260F be available?

It’s available in 22.5 and 24.5 standard and low profile sizes. Ask your dealer for more information, or check the box on the business reply card in this issue of Real Answers for a brochure on the R260F. It’s just the thing for stretching tire life in high scrub applications.

A free brochure on the R260 is available
from dealers, Bridgestone Representatives
or by requestingone from the Tire Doctor
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