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.