Executives talk rolling resistance at ITEC In Focus

CUYAHOGA FALLS, Ohio—Many factors are considered when purchasing tires. And other factors must be considered when manufacturing tires.

At the inaugural ITEC In Focus: Testing Innovations conference, held Sept. 16-17 in Cuyahoga Falls one of the hot topics was rolling resistance, both its history and the topics being debated within the U.S. government and the industry.

Marion Pottinger, owner and president of M'gineering L.L.C., kicked off the rolling resistance conversation by stating that the pneumatic tire was invented twice.

“We think of tires as a piece; they're the fundamental piece,” he said.

The first invention was by Robert William Thomson in 1845, who was working with horse-drawn vehicles. “Rolling resistance was immediately investigated because of the ease of rolling pneumatic tires,” Pottinger said.

Thomson noticed that it was easier to roll his horse-drawn vehicle on his tires than it was on the existing wheels. He then hired other engineers in Scotland who did a rolling resistance test.

“They used big spring scales between the horses pulling the vehicles and the vehicles,” he said.

While the tests showed these pneumatic tires had better rolling resistance, the idea did not sell well.

A little while later, as the bicycle evolved and people started to ride them for transport, John Boyd Dunlop invented the tire for the second time. He also did some rolling resistance tests with his new design. Previously, there was a hard rubber tire on the bicycle, but he realized he could roll his design across the yard, Pottinger said.

Rolling resistance has come a long way since the 1800s, but it is still a topic discussed often in the industry. Pottinger served on a panel, along with Larry Evans, principal, Larry Evans Consulting, and Gerald Potts, CEO and chief technology officer of TMSI L.L.C., a Mesnac Co., to discuss the current state of rolling resistance.

A common theme was that the European market's rolling resistance efforts are changing the game, but the U.S. is trailing behind the standards.

“To quote myself at an ITEC a few years ago, the project moves at the speed of government,” Evans said. “The rolling resistance standard in the United States has been delayed to at least 2017.”

He did explain that some things definitely will happen, including one test that will be the ISO 28580 procedure.

Evans said most likely Smithers Rapra will be the reference lab for the U.S. for regulations, so everything will be referenced to its data. However, it is unclear whether the data referenced will be Smithers' raw data or whether it will be Smithers' data corrected to the European theoretical tire for which it referenced the data.

Additionally, it is probable, but not official, that the U.S. will adhere to the same measurement bins as Europe. “(The National Highway Traffic Safety Administration) has no authority to ban tires, so unlike Europe, they won't be able to ban any high rolling resistance tires,” he explained.

Evans added that while these efforts are in conjunction with the EPA, Congress would have to designate the EPA as the regulatory agency for enforcement to change that situation.

At this point, it is a “consumer information only” sort of regulation.

Potts added that Europe enacted its regulations on Nov. 1, 2012. With that bin system, tires greater than 12.0 rolling resistance coefficient are not going to be sold in Europe. In the U.S., the government has no authority to ban the sale of those tires. Additionally, on Nov. 1, 2018, Europe is banning tires with more than 10.0. In Europe's system, those were tires labeled Gs and Fs. In the European system, there is no D, so there will be an A, B, C, E system.

Potts said no one knows where things stand today, because things have changed so much because of Europe.

In the realm of tire labeling, the U.S. also is trailing. Europe already has a system in place, and reports say China is about to adopt a tire labeling system as well.

Evans explained that when he worked with NHTSA, it published a proposal for a tire labeling scheme, and it has been greatly debated. He said the final rule has been delayed until at least 2017. While NHTSA was mandated by Congress to do this years ago, it is a small, busy agency.

“They only have about 40 actual working engineers in the entire agency responsible for the safety of all the vehicles and all the vehicle components,” Evans said. “They are very busy doing recalls at the moment.”

The regulation does have a rolling resistance portion, he said, which will correspond to the European system. It has a wet traction rating, which was proposed to be different than the current UTQG rating. Evans said the current UTQG rating doesn't have very many divisions and it is a sliding wet traction, which was acceptable before automatic braking systems. With ABS, peak braking is what is important.

“They are way behind the rest of the world,” Evans said. “They actually were the first to publish a proposal and the last to actually implement it.”