Grassroots Motorsports
Issue link: http://grassrootsmotorsports.epubxp.com/i/501675
Grassroots Motorsports 125 Bridgestone is a large tire maker that has always had an interest in motorsports and high- performance tires–and at all levels, too. Throughout their history, they've veered in and out of the autocrossing world as their products and marketing plans synched up with our community. Not long ago, they were top dog in this category with their RE-01R and RE-11 follow-up. Two years ago they released the updated RE-11A, but it didn't quite get them back on top. As a result, for 2015 we have the all-new RE-71R. In addition, they're back with 18-wheeler event support crews and contract driver programs. Is this tire one that deserves all the hype? Oh yes. While it may or may not be the best tire for a given situation, it is cer- tainly a player to be strongly considered T h e f i r s t s i g n s came on the skidpad, where we suddenly dropped into the 9.6- and low-9.7-second range. However, like the Dunlop, this tire was very pressure-agnostic, produc- ing similar results over a wide range. It also had some tem- perature sensitivity, but not nearly as much as the Dunlop. After their runs on the practice course, both drivers came back smiling. David again praised the compound loading, and on a couple of flyer laps he found lots of time in the challenging sweeper entries. He also found more confidence in the slalom than he had on any other tire tested. Andy pro- claimed the longitudinal grip–braking and acceleration–the best of the bunch, and this trait should suit high-horsepower cars nicely. Another key point to note is the dif- ference in our drivers' times. On the other tires, David's familiarity with the car and course constantly had him ahead by a sizable margin. This time, though, the gap shrank. This data point might mean that the Bridgestone is the most intuitive tire and covers up any handling quirks. Here's how Andy summarized it: "All the goodness of the Dunlop, w r a p p e d i n a g r i p p i e r compound." And if you compare the two closely, they sure look the same from the outside: simi- lar crowned profle and tread design. Coincidence? Bridgestone RE-71R average run best run best lap expert driver: 48.6 48.3 23.8 guest driver: 48.7 48.6 24.0 (all times in seconds) magical 195. We are confdent, however, that the class of 2015 has moved beyond these two. Looking forward, Kumho is scheduled to fnally release its long-awaited–and unfortunately named–V720. It's actually a suc- cessor to the Ecsta XS, a GRM test winner a few years back, but the V720 name suggests a relation to the successful V710, a true slick-design R-comp. This is not the case. While this tire has been avail- able in Asia for several years now, Kumho has been tweaking it relative to the market competition for introduction here in the U.S. Release is described as imminent. We'll test them as soon as we get our hands on a set. FEATURE: STREET TIRE TEST