SAN FRANCISCO, Cal. - Michelin's annual Bibendum Challenge gathers the world's most environmentally friendly and fuel-efficient vehicles in a friendly competition that highlights some of the most adva...
SAN FRANCISCO, Cal. – Michelin’s annual Bibendum Challenge gathers the world’s most environmentally friendly and fuel-efficient vehicles in a friendly competition that highlights some of the most advanced technologies in the world.
This year’s event, held in Sonoma, Calif. included commercial vehicles for the first time. Natural gas, advanced diesels, hybrids and fuel cells were everywhere, but “out back,” specifically on the drive axles of a very high-tech CNG Freightliner, was a technology that promises real-world improvement in fuel economy, off-the-shelf: wide-base tires.
The Michelin X-One tires on the tractor are part of a small but growing subsector of the industry that’s looking for efficiency through a combination of lower rolling resistance and lighter weight.
They offer some significant advantages.
The most obvious is weight.
Because one tire and wheel replaces two, using wide-base singles can increase legal payloads significantly.
Weight savings are typically 200 pounds per axle, which translates directly into added revenue-producing payload.
In gasoline tanker service, for example, a fully wide-single equipped combination would allow about 130 gallons of extra capacity per tank.
Another advantage for bulk carriers is wider spacing between centres, allowing trailer designs that place the load lower, reducing the centre of gravity and increasing cargo volume. For most operators, however, new tires need to work with existing equipment, and as a retrofit, it’s all about fuel economy.
“You take a giant leap forward in improving the fuel efficiency of a vehicle’,” declares Ralph Beaveridge, Michelin’s Canadian marketing director for truck tires.
“For example, we just changed the drive tires on a tractor, a typical six-by-four configuration, where we start as low as 2.3 percent improvement in fuel economy. 2.3 percent isn’t a lot when you think about your car, where you’re driving a $30 tank a week. But for a fleet that’s spending $30 million dollars a year on fuel, you get an impact on the bottom line. We say starting as low as 2.3 per cent because there are some tires that are extremely fuel efficient in duals that are not popular in Canada because those particular designs don’t offer the kind of traction that our drivers expect and demand. When we compare with the tires that are running typically in Canada just on the tractors, we see numbers as high as 10.2 per cent. So for an owner/operator that becomes something that jumps out at them fairly quickly.”
The savings are significant and are confirmed by tests from Michelin’s competitors such as Bridgestone, who note that wide singles are more fuel-efficient than conventional or low profile duals.
Retrofit costs can be a factor, but on a new-fit or complete axle replacement basis, costs are very competitive with dual assemblies.
As for safety, single tires don’t have the obvious redundancy of duals, but Michelin has performed tests at highway speeds with singles rigged to blow out suddenly, and reports that tractor-trailer combinations with wide singles are as controllable as conventionally- equipped units whether the blowout happens at the trailer or drive positions.
Of course, limping into the next stop isn’t possible with a single, but with a loaded combination, the resulting abuse of the remaining tire on the dual will likely kill the casing anyway, so there may not be an economy compared to a service call. Tread life is at least comparable to duals, too, but what about retreading?
“We retread them. We have the Michelin retreading technologies, MRT, with four franchises currently in Canada, and one in Ontario called Town and Country Retreading in Ingersoll,” says Beaveridge.
“None of the Canadian franchisees currently retread X-One tires because we don’t have the market for them in Canada yet, due to the regulatory restrictions on those tires. But we do have facilities in the United States that are producing them and we are bringing them into Canada for customers that are using the new tires and want it retreaded on their casing. That’s more of an exceptional transitional element. We’re very confident that with the evidence of what this tire can do, that various provincial governments and regulators will help Canadian trucking modify regulations without the handicaps they are facing in Canada.”
Are wide singles in your future? Prototypes existed in 1960, but today, Michelin, Bridgestone-Firestone and Goodyear have developed the technology. As OEMs jump aboard, wide-base singles may finally be ready for prime time. The fuel and money you save will be your own.