April 26, 2012
Technology with a-peel
Yokohama takes advantage of orange oil properties
The Yokohama Avid Ascend enters the grand touring tire segment in 45 sizes.
The use of orange oil in tires is not a gimmick or magic. Yes, it replaces some petroleum-based oils in the compounding, which is good for the environment. But it also helps the tire grip without sacrificing tread wear and fuel economy.
It also is not a trend. Only Yokohama Tire Corp. uses orange oil in its tires. That includes the new Avid Ascend all-season grand touring tire.
Orange oil — derived from orange resin from the orange peel — has the ability to keep rubber soft without making it more hysteretic. To explain, Pat Keating, manager of technical engineering, uses the example of a rubber ball losing energy while it is bouncing.
If you drop a rubber ball, it will bounce, but not as high as the distance from which you dropped it. The height will decrease on each successive bounce until the ball is lying on the ground.
In essence, the ball loses energy during every bounce until there is no energy left and it stops moving. The same thing happens to a tire in motion: Energy is lost as it rotates. In a vehicle, however, the engine replaces all that lost energy, and the tire continues to move the vehicle forward.
Compared to petroleum-based oils, orange oil is less hysteretic, which helps the Ascend roll more freely.
“We also achieve low rolling resistance through the Ascend’s advanced profile design and tread pattern design,” says Keating. “And the gripping properties of orange oil allow us to do that.”
Bob Abram, product planning manager, says it is possible that orange oil eventually will be used in all Yokohama tires. “The goal of our Japanese engineers is not the use of orange oil specifically, it is the use of whatever is required to meet our goals.”
45 sizes initially, 49 eventually
According to Yokohama, the Avid Ascend’s main competitors are the Goodyear Assurance ComforTred Touring and Michelin HydroEdge (Michelin North America Inc. recently announced it will replace the HydroEdge line with the new Michelin Defender).
Abram says the biggest trend in the touring tire segment is higher speed-rated sizes. Almost half of the replacement sizes are H-rated and higher.
The Avid Ascend is available in 45 sizes manufactured at Yokohama’s Salem, Va., plant. The tire is backed by the following tread wear warranties: T-rated, 85,000 miles (the highest Yokohama warranty ever); H-rated, 75,000 miles; and V-rated, 65,000 miles. Here’s the size breakdown.
15-inch (11): 175/65R15 84T to 215/70R15 98T.
16-inch (16): 185/55R16 83H to 235/65R16 103H.
17-inch (13): 205/50R17 93V XL to 235/65R17 104H.
18-inch (five): P215/55R18 94H to 235/55R18 100H.
Four more sizes will be added later in the year, including 235/50R19 99V.