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Things change quickly in the world of 200tw street tires. With so many motivated manufacturers vying for a share of a myriad of motorsports venues, today’s cutting-edge technology is tomorrow’s also-ran.
During the last 20 years, BFGoodrich, Bridgestone, Falken, Kumho, Toyo and Yokohama have all cycled through as the dominant brand, with Bridgestone returning to prominence in 2015 with its Potenza RE-71R. Thanks to an almost perfect blend of response, grip and longevity, Bridgestone built a huge following for both motorsports and street use.
[Ultimate track tire guide | 200tw, 100tw, street-legal track and R-comps]
The RE-71R was filling podiums in autocross, time trials and even endurance racing. But when 2020 came around, word filtered out that production of the RE-71R had ceased, and there was no replacement coming to the U.S. Amateur racers throughout the country were stunned.
[200-Treadwear Tire Test | Goodyear F1 Supercar 3 and Michelin Pilot Sport Cup 2 vs. the Outgoing Bridgestone RE-71R]
Well, race fans, happy days are here again: Bridgestone is back. Its new Potenza RE-71RS was developed in Japan specifically as a track day tire with little consideration for the wider U.S. market–but that’s how its predecessor came to be, and that one turned out to be quite versatile.
Would the RE-71RS share that same versatility or would it be a one-trick pony? As a source confided in us, that was a key concern for Bridgestone’s American arm and a reason why the company didn’t initially import the new tire.
During Bridgestone’s two-year hiatus, fans looking for the same type of responsive feel gravitated to the then-new Falken Azenis RT660. There they found similar performance, especially when compared to alternatives from Yokohama and BFGoodrich.
[200-treadwear tire test | Falken RT660 vs. Yokohama A052 vs. Nankang CR-1]
This shouldn’t be a surprise, given that the Bridgestone and Falken employ similar internal belt packages and tread design. Comparing the new Bridgestone against the Falken seemed the most appropriate.
Not all the sizes on the new Bridgestone’s roster would be available on day one, but we were able to score a set of 245/40R17 tires early–the perfect size for our Triple Threat ND-chassis Mazda Miata. Why a Miata for tire testing? We’ve found that the larger the performance envelope, the more dangerous and challenging it becomes to take unknown tires right to the limit and keep them there. Our experience, however, tells us that the relative results do scale up.
For the Falkens, we went with the 235/40R17 size, the variance coming from the desire to keep the tread width the same. The Falken runs very wide, with the 235 putting down the same contact patch as Bridgestone’s 245. We mounted up all the test tires on 17x9-inch 6UL wheels from 949 Racing.
Harris Hill Raceway again served as the test grounds. Running it counterclockwise provides a good mix of big sweepers, tighter 180s and two long straights ending in hard braking events. Both sets of tires were given a first heat cycle several days before the test.
Test day dawned partly cloudy with temps in the mid-80s. Fortunately, the track was relatively clean and rubbered in from heavy use the previous four days. We unloaded and got right down to business.
Track Results
Falken Azenis RT660
- best lap: 1:29.4
- $234 (235/40R17)
Since we’ve run them before, we first went out on our fresh Falkens. Solid grip, responsive handling and a fairly talkative nature are its strong suits, and we felt right at home. On this warm day, our first three laps were the quickest before heat soak caused a reduction in grip, slowing us about half a second for several more laps.
Bridgestone Potenza RE-71RS
- best lap: 1:28.1
- $228 (245/40R17)
We then headed out on the Bridgestones and immediately noticed a stronger on-center feel, receiving more tactile feedback with lateral loading. Even more impressive was the exceptional combined loading under trail braking and corner exit power-up. Those acceleration gains paid dividends down each of the three straights, which added up quickly in our underpowered Miata. The first lap out on stone-cold tires produced a time that was more than a second quicker than the Falken’s best. The next two laps also beat the Falken yet were substantially slower. Subsequent performance then stabilized at times similar to the Falken’s.
Falken Azenis RT660 (retest)
Bracketing our test to look for track or driver improvements, we headed back out on the Falkens. Average times were just a couple tenths quicker, but all the dots connected well on the second pass for a single flyer. Data analysis of that lap later showed driver confidence improvements in two very tricky areas: the high-speed entry to the Turn 8 sweeper and the trail-braking zone into Turn 2. Overall, though, the relative rankings were clear.
Bridgestone Potenza RE-71RS (retest)
We could have packed up at this point, but we were curious about that cold-tire “magic lap” delivered by the RE-71RS. Could we repeat it even though the tires were no longer as cool as when we first started the day? We headed out for another session and came up just a couple tenths short. But we did do it twice in a row this time before times again fell off.
Who Won Here?
Bridgestone Potenza RE-71RS (left) and Falken Azenis RT660 (right). Photography Credit: Andy Hollis
The day’s results took us by surprise at first, as we expected a much closer battle. In fact, previous sessions with this car on RT660 tires under similar conditions produced lap times that rivaled the new RE-71RS.
What was different this time? Tread depth. In addition to benefiting from heat cycling, the Falken performs better at lower tread depths. In the past, our quickest times have always come once the tread got below 4/32 inch.
Of course, the RE-71RS may very well find even more time once worn or shaved. That said, its predecessor, the RE-71R, did not improve significantly at lower depths. Which will it be? The answer to that question will have to wait for another day.
But Bridgestone has built another winner. We love how this tire feels on track, and its early lap heroics bode well for both time trial and autocross competitors. While we wish we hadn’t had to wait, sometimes you need to. Welcome back, Bridgestone.
Comments
So, some behind-the-scenes info.
Our test tires only landed in the U.S. around June 24. Bridgestone needed a few to unload and ship them our way. They arrived at Andy's shop late this past Thursday.
Tires had to be mounted and balanced. Then we could heat cycle and allow the tires 24 hours to cure. Testing took place yesterday. Then figure a bit for data analysis, writing, editing and proofing. Whew.
We have some wider ones on the way, too, but they're still on the way.
I run the kumho v730 and appreciate the fact that it's pretty fast and consistent for autocross, TT, and extended HPDE sessions. I was hoping the Bridgestone would be more similar to the v730 than the a052. I'm also surprised the rt660 fell off after a few laps because many folks say it retains speed. Perhaps tread depth is a key variable here. The v730, with so little tread, doesn't heat up as quickly and the compound likes heat so no surprise it tolerates extended lapping.
So you haven't yet run the RE-71RS head-to-head against the A052?
In reply to jstein77 :
Yes we did--it's the sidebar next to/under this story depending on what device you're on.
JMcD
New Reader
7/7/22 10:12 a.m.
Y'all are the best. Did the autocross tires get the same heat cycle treatment as Andy's?
I appreciate what you're trying to do with the 235 vs 245, but I think it misses the point quite a bit. No sanctioning body I'm aware of normalizes for measured tire width, they class based on stated tire size.
IMHO this makes the more relevant comparo a 245 vs 245, even if the 660s run significantly wider because they end up living in the same class.
Instead, there needs to be some reading between the lines that the re-71rs is still faster 245vs245, but it's a guess instead of real data.
G_Loc
New Reader
7/7/22 1:20 p.m.
Any idea when wider sizes will be available? I had ordered 295s from Tire Rack on 4/20 right when they became available. Delivery date was supposed to be early June, then got pushed back to July, and now there's no ETA at all. Heck they don't even show up as an available size anymore. Had to go with an alternate tire for the time being.
In reply to G_Loc :
Sorry, I don't have any info regarding future shipments.
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