The “shape” of things to come. Wayne Gerdes – CleanMPG – July 26, 2017 We have seen similar very tall and thin tires on the BMW i3 which uses P155/70R19 Bridgestone Ecopia EP600s. Could they be standard equipment someday? This video comparison depicts a real world coast down test between a car with conventional tires and another with tires using ologic technology to evaluate the reduction effect of rolling resistance. "ECOPIA with ologic" is a new tire with Bridgestone technology aiming for the coexistence of superior fuel efficiency and safety by enlarging the diameter and narrowing tread width. The large diameter of the tire controls the deformation, which helps in reducing rolling resistance. As an effect, this will result in improving better fuel efficiency of the vehicles. Additionally, air resistance is also reduced due to the narrowed tread width. Furthermore, high grip performance on wet and dry surfaces is obtained by a long, grounding shape with an unique pattern and compound put together. In general, various resistance such as rolling resistance and aero-dynamic resistance act on a vehicle against its motion. Reducing resistance of any type will allow a vehicle to move with less energy which in turn improves fuel efficiency. Rolling resistance on tires is a force that acts against a vehicle’s traveling direction. It is primarily caused by the deformation of the tires while rolling. For instance, assume you are pedaling a bicycle; If the air pressure in the tires was low, you would have to exercise greater power on the pedals in order to move forward. This is because the rolling resistance on the tires is enhanced due to its increased deformation. ologic: “Narrow tread” + “Large diameter” + “High inflation pressure” = “Superior fuel efficiency” The Bridgestone Group’s fuel-efficient tire technology, named “ologic,” produces superior fuel efficiency with the following two features: Large tire diameter and high inflation pressure to significantly mitigate deformation of a tire in contact with the road surface and thus reduce rolling resistance Narrow tire width to reduce aero-dynamic resistance, which is an important factor in the improvement of a vehicle’s fuel efficiency With optimizing rubber compounds and low heat production silicas in the reinforcement layers, tire structures and tread patterns, a 30% reduction of rolling resistance coefficient along with a 10 % improvement of braking on wet road has been achieved compared with a conventional tire. These results were based on a comparison between a tire with the ologic technology (tire size: 155/70R19, inflation pressure: 46 psi) and a conventional tire with an equivalent load capacity (tire size: 175/65R15, inflation pressure: 30 psi). I sure would like to see the difference when both are set at the same psi. It would be hard to use these tires on most cars today given the larger outside diameter which would cause interference inside the wells both on the height basis and when trying to turn. But, I would love to drive them. I suspect ride quality may be sacrificed some as well. I would still love to have some of these in 15 or 17" diameters to try on the cars we do drive today.
Very nice! I have to say that my Leaf with either the stock Ecopia EP22 or with the Nokian Hakka R2 winter tires - is BY FAR the best coasting vehicle I have ever driven. I have both inflated to about 42-44PSI. 30PSI is way too low; but they did this for a dramatic difference, I guess. My brother's i3 REx is pretty good - but with it's 1-pedal setup, it is harder to coast consistently. The other issue with it's Ecopia tall narrow tires - is tread wear. They only last 17-19k miles.
Good, a return to sensibly proportioned tires like we enjoyed circa 1930---or even 1990 to a lesser degree. Unfortunately, today's fashion police won't tolerate them.
Hi Bill: In some of the PR through an infographic, Bridgestone stated dry braking was also improved. Wayne
It's hard to see any reason for that unless the tread compound is softer. However, I'd bet hydroplaning resistance is much improved, assuming equal tread depth, etc.
In 1980 , I predicted that all cars would go to tall, skinny wheels and tires. I was , quite obviously , wrong. I always liked the tall skinny ones on air-cooled VW's , and I certainly noticed what the BMW i3 uses.
I think the 195/65-15s pumped up are just fine and are in widespread use amongst the "eco" vehicles. They're also less expensive to replace.
"ologic" vs. "OLogic" - the latter is an existing company's name... I wonder if there will be problems with using "ologic"...
Yeah , and mine are pretty well "pumped up " ( 45 psi , sidewall = 44 max. ). I do remember having some mighty skinny tires on my 87 Nova ( Corolla). They were 155/80R-13's. But that car only had 74 HP , so it was plenty of tire.
I wouldn't call that skinny. 145/80-13s were common on lighter cars then and earlier. My Subaru and Mazda both had 155/80-13s although considerably lighter than some later cars that had 145s---but should've and would've had at least 155s if the manufacturers hadn't been pinching pennies so hard.
My GLC had the "fatties" (175/70R-13). It was the "Sport" model. It did have some nice features , like map lights and a quartz analog clock that kept PERFECT time. And still got 47-49 MPG at 57 MPH.
