Bridgestone Dueler H/L 422 Ecopia; photo courtesy Bridgestone. Click image to enlarge
Review and photos by Grant Yoxon
Phoenix, Arizona – There could be an eco-friendly low rolling-resistance tire in your future – even if you don’t own a hybrid.
Until recently, low rolling-resistance tires were usually found as original equipment tires on hybrid vehicles like the Toyota Prius and Honda Insight. Their use helped these vehicles achieve lower fuel consumption than they would have with conventional tires.
What are low rolling-resistance tires? If you take two vehicles, one with conventional tires and one with low rolling-resistance tires, and free-roll them – with no mechanical input – down a slope, the one with low rolling-resistance tires will go further than the one with conventional tires with the same amount of energy input. Low rolling-resistance tires minimize wasted energy as a tire rolls. This is how low rolling-resistance tires contribute to better fuel economy.
Of course, there was a price to pay. The wet and dry performance of low rolling-resistance tires was typically worse than that for a similar conventional tire. Simply stated, they had less grip. And they would wear faster than a conventional tire.
Advances in tire technology promise to change that, making low rolling-resistance tires more suitable than ever as a replacement tire. And on almost any vehicle, not just as original equipment on a hybrid.
Bridgestone EP422 Ecopia. Click image to enlarge
Bridgestone recently launched two new low rolling-resistance tires – the Ecopia EP422 for fuel-efficient vehicles and the Dueler H/L 422 Ecopia for SUV, CUV and light truck applications – that incorporate technology that improves grip and extends tire life.
NanoPro-Tech (short for Nanostructure-Oriented Properties Control Technology) is a Bridgestone proprietary technology first introduced in 2006 and continually refined since that controls the interaction between polymer, filler materials such as carbon black and silica and other rubber chemicals at the molecular level to increase grip and reduce heat.
In a conventional tire, carbon molecules can clump together which causes friction and generates heat. With Ecopia tires, the microstructure of the polymer is controlled by NanoPro-Tech which keeps the carbon molecules dispersed, minimizing energy loss cause by friction between carbon molecules.
NanoPro-Tech is a core Bridgestone technology and not limited to eco-friendly tires.
The Ecopia line of tires also incorporate what Bridgestone calls a “fuel saver sidewall.” The fuel saver sidewall compound lowers rolling resistance by returning more energy back to the tire, rather than losing that energy as heat, than a normal sidewall.