Photography Credit: Anna Overman
Once upon a time, we had race tires and we had street tires, and all seemed right and easy with the world. Today, well, we have a number of options. So. Many. Options.
Want a street-capable tire that consistently delivers lots of quick laps over a long period? Choose from the Endurance 200 class of tire. Want to win an autocross or time trial yet still be able to drive safely to and from the event? A Super 200 tire is your hot ticket.
What if your steed is trailered but rules require a DOT-approved tire? The market offers a range of competition-ready R-comp tires. No rules restrictions and ultimate pace is your goal? Go with a pure racing slick.
How do these different classes actually compare, though? Is the progress through the steps linear or does one step represent a bigger jump? To minimize variables, we performed some intramural testing based on one brand’s offerings.
Thanks to a long and diverse history of motorsports involvement at all levels, including the steps common in our current scene, Yokohama was a natural choice. The company offers two different 200tw models plus an R-comp and a dedicated slick.
For this comparison, our test mule would again be our Triple Threat ND-chassis Miata, and we’d turn laps at Harris Hill Raceway. Tire sizing was our usual 245/40R17 mounted to 17x9-inch Kogeki wheels from Flyin’ Miata. The lone exception was the Advan A005 racing slick, as it uses dimensional sizing that doesn’t correlate exactly to standard street tire sizing–more on this later.
Since the AD09 and A055 were already six-lap veterans from previous tests, no additional prep was needed. We gave the fresh A052s the usual heat cycle with a 45-minute drive to the track and back, plus six laps of ever-increasing intensity. For the slicks, we chose no prep since this type of tire typically delivers its quickest laps as stickers.
Test day dawned cool with an overnight low in the 40s. All of our test tires were kept cozy in our motor home at room temperature until called into action. We ran the AD09 first to clean the track of overnight dust accumulation until lap times stabilized. A half-hour coffee break allowed those tires to cool again before we started the timer. Ambient temps had risen to the 50s and would reach as high as 68 by the end of the day’s work.
Tire Specs
From left to right: Yokohama Advan A005 (racing slick), Yokohama Advan A055 (R-comp), Yokohama Advan A052 (Super 200), Yokohama Advan Neova AD09 (Endurance 200)
Yokohama Advan Neova AD09
For dual-purpose cars with more emphasis on street use.
fastest lap: 1:28.0
Our experience with this model’s lineage now goes back nearly 20 years, with the introduction of the Advan Neova AD07 to the North American market in 2005. Thanks to a patented micro-silica compound, it delivered tremendous dry grip and durability for a street tire. It found a home in SCCA Street Touring autocross and became the original fitment for the Lotus Elise.
In 2009, the updated AD08 saw a performance increase, followed by an even quicker AD08R in 2013–the R indicating its “revolutionary” compound. That tire was so good that it remained in production until the arrival of the AD09 in 2022.
on the road: In addition to achieving cone-dodging success, these 200 treadwear tires have also found their way onto dual-purpose track day cars, where they deliver a strong blend of pace, consistency and durability in both wet and dry. Combined with a responsive, athletic feel on the road, the Neova remains a true do-it-all tire.
on the track: After taking a full lap to come in, its ultimate grip was not nearly as high as the others, and the edginess made it hard to hit all of our marks every lap. Still, the tire itself hung in there, losing no performance over the full session. We’d call it consistently playful. While the AD09 required a lot of steering input and felt edgy at the limit, recovery was always quick and intuitive.
Audible feedback was ever-present once the tire was up to temp, clearly announcing pushes to the limit. Toward the end of the session, the intensity of the feedback increased as the tire began to mildly heat soak.
Yokohama Advan A052
A streetable motorsports tire for autocross and time trial use.
fastest lap: 1:26.0
Japan and Europe have more stringent rules for street-legal track tires. Instead of our nearly slick R-comps, these overseas markets require more of a tread.
Yokohama has a long history in this area with models such as the A022 (1990), A032R (1994) and A048 (2000). American versions of these tires sported very conservative UTQG treadwear ratings to market their dry grip focus.
2016 saw the introduction of the latest in this line, the A052. It carried a 200 rating, but thanks to its initial tread depth of 6/32 inch, it wasn’t legal for much of the day’s American motorsports scene. That all changed in 2019 as Yokohama deepened the tire’s grooves to meet the 7/32-inch minimum required for the SCCA and others. With this, Yokohama moved straight to the top of the Super200 category in the U.S.
on the road: The A052 offers a soft feel and a somewhat vague steering response. Unlike most 200tw tires, however, the ride quality is quite good. At full tread depth, it’s also very good in wet conditions provided no deep puddles are present.
on the track: This is where the A052 really shines, with tremendous grip being its strong suit. Corner exit power up is unmatched in the category, while lateral grip is among the best–that is, until it heat soaks. Typically, it’s a one-and-done tire in warm ambient conditions, with falloff coming shortly after the first full send lap.
Heat soak can be mitigated through lower tread depths either from wear, shaving or, in the case of this test, a cold track. So while we did experience some falloff, it wasn’t nearly as severe as we’ve seen on warmer days.
Yokohama Advan A055
Despite the DOT rating, these are billed as for motorsports only.
fastest lap: 1:24.4
The DOT-compliant R-comp tire category is unique to the U.S. market and is the result of decades of manufacturer competition. Limited only by the minimal U.S. government regs for street use, R-comps are close cousins to full racing slicks. In fact, despite that DOT rating, all are clearly marked as “Not for Highway Use.”
Hoosier has long dominated this segment with its A7 and R7 tires–one for autocross, one for road racing. Yokohama recently joined the fray with its A055, a tire that matches the R7 in pace but offers more precise handling characteristics.
on the track: The A055 came up to temp rather quickly, and full grip was available after about a lap and a half. Steering response felt extremely progressive, with small inputs making increasingly larger turning moments as cornering loads increased.
Breakaway was a little edgy, especially at the rear of the car. This required constant attention to drive at the limit consistently, but the tire’s pace never slowed. Data showed that we truly connected all the dots on that final flyer.
Yokohama Advan A005
Highly optimized for competition use only.
fastest lap: 1:25.4
How about a tire with zero concessions for street manners? Enter the world of racing slicks.
Street tires are molded with patterned void areas to help resist hydroplaning in wet conditions. But those tread blocks reduce dry performance through squirm.
In the early days of motorsports, teams shaved off most of that tread to produce a faster tire. Eventually, racing tires came molded with only a smooth tread surface. These tires are commonly called slicks.
That smooth tread cap has also been reduced in thickness–typically only 4/32 inch–which further mitigates heat buildup under load. This in turn allows for much softer, stickier compounds to be used without graining.
Today’s racing slicks are highly optimized for specific applications and available in a variety of compounds to suit the requirements of pace and durability. Where street tires, even R-comp models, are often billed as a one-fits-all solution, slicks can be tailored to a specific application. It’s basically the ultimate expression of optimization for purpose–but at the expense of wider range of use.
Not every compound is available in every size–again, back to that specialized mission statement–but for maximum effect, we wanted to try the softest compound available, figuring it would offer the fastest times.
Racing slicks typically use dimensional sizing rather than the aspect ratio system found on street tires. Within the A005 size lineup, the closest match in width to our 245/40R17 street tires is a 240/640R17, but the outside diameter is a bit too tall. Plus, this option only exists in a medium compound.
The next size down–210/610R17–is both shorter and narrower but comes in the soft compound. Our experience has always been that compound beats size–except in extreme cases–so we ordered up the smaller, stickier tires.
Our excitement diminished a bit when we were informed that no fresh inventory existed–the A005 is much more prevalent in larger sizes–but Yokohama did have a set that was a few years old. Given that our A055 tires performed well despite a 2-year-old build date, we gave the go-ahead. Upon their arrival, our anticipation took another hit: These tires looked even older. In fact, the stickers had yellowed.
on track: Our suspicions were confirmed, as these tires were no longer in their prime. They required a lot of warmup to deliver any grip at all, though they were fairly consistent afterward. The driving dynamics were quite good, with even more responsiveness than the lively A055. But the grip just was not there to deliver the goods.
While not all slicks carry a DOT-style date code–manufacturers can look up batch codes to verify builds–our A005s did indeed carry one. And that date code was full of bad news: Our tires were more than 5 years old.
Even when warehoused properly, the compounds used to make racing slicks usually don’t age well. These tires were the equivalent of a skunked bottle of wine, compromising part of our vertical tasting. We’ll have to revisit this one as, based on our experience, the racing slicks should have outpaced the R-comps by upwards of a second.
fastest lap: 1:28.1
At the end of the day, we re-ran the AD09 to properly bracket for both driver and track stability. Even with the warmer conditions, the lap times were very similar. The only variation was quite a bit more audible feedback, bordering on a screechfest. Happy with our data, we packed up.
Reviewing our back-to-back times with this slate of tires, we found this experience very enlightening. The AD09 is now one of our favorite track-capable road tire recommendations, while the A052 continues to find a place on our cars for competitions with 200tw restrictions. We’ve also found podium success running the A055 in NASA TT, where the rules favor DOT R-comps.
The A005? Well, the jury’s still out on that one, but we have high hopes based on the quality of the rest of Yokohama’s offerings–next time, we just need to test a current size.
The big lesson here: This test showed how each class of tire delivers specific traits. Wondering how much time you’re giving up by not running the fastest tires allowed by your rules? This little exercise might shed some light.
Track Results
I anticipate buying a car in a few months that will serve as my motorsport platform for the foreseeable future. I plan to drive it to local events though I may trailer it to tracks that are further away. I've been reading the GRM Ultimate Track Tire Guide for a while but I'm still not sure what tire I'd like to run, at least initially. Any recommendations?
Hankook RS-4 is what we use for an endurance tire but it also makes an excellent track day tire. Consistent over the lifespan and last far longer than I would have believed. For the money it's pretty decent and seems better and cheaper than the Toyo R888R (which I also quite like). I tried a set of Federal ZM-201M and did NOT like them. Took forever to warm up (no grip cold) and never got great grip out of them... of the flip side, they last forever.
Are you competing? If so, what class/org?
If not, how important is pace versus longevity?
Do you care about wet performance either on the street or track?
Is it typically cold or hot where you run?
The answers to these question, along with the chart in the Guide, will narrow down the choices.
Andy Hollis said:Are you competing? If so, what class/org?
If not, how important is pace versus longevity?
Do you care about wet performance either on the street or track?
Is it typically cold or hot where you run?
The answers to these question, along with the chart in the Guide, will narrow down the choices.
I expect to compete in some time attack/time trial events but that will not be the car's primary purpose. Initially longevity may be more important but as I develop the car outright pace will take priority. The car will likely never see wet weather so only dry performance is a consideration. I live in Michigan. It will be cooler at the beginning and ends of the season. Part of the choice will be cost and ease of getting the tires.
QuikMcshifterson said:Hankook RS-4 is what we use for an endurance tire but it also makes an excellent track day tire. Consistent over the lifespan and last far longer than I would have believed. For the money it's pretty decent and seems better and cheaper than the Toyo R888R (which I also quite like). I tried a set of Federal ZM-201M and did NOT like them. Took forever to warm up (no grip cold) and never got great grip out of them... of the flip side, they last forever.
Thanks!
Looking at the first chart, it's amazing how much weight savings a racing slick offers over an Endurance 200. Even Endurance 200 vs. Super 200.
J.A. Ackley said:Looking at the first chart, it's amazing how much weight savings a racing slick offers over an Endurance 200. Even Endurance 200 vs. Super 200.
When you don't have to worry so much about real-world puncture resistance or pot-holes, you can leave a lot of steel out of a tire.
You can thank Firestone and the Ford Exploder crisis for that.
And if you think these slicks are light, next time you are at an IMSA race, go to the Michelin tent and pick up one of their "Confidential" slicks. Super high-tech internals like Kevlar for even lighter weight. All that comes at a cost, though.
Andy, question for you to see if I'm evaluating the data correctly.
Looking at the tread pattern, the Conti ExtremeContact Force would appear to be more dry-fast focused than the Conti Extreme Contact Sport (or Sport 02). But the chart would seem to indicate that the Sport is equally fast in the dry while faster in the wet, but wears more rapidly. Given the more rapid wear and better wet performance of the Sport, my gut says that the Force is about the same dry performance because of the tread shape despite the harder compound - fair conclusion?
I'm really just surprised that the Force isn't markedly faster in the dry but I guess that's the trade off for longer wear. Thx.
For our first race in 3 years I just bought the Maxxis VR1s. We loved the RS4s but none were available in our size and the last tire test said the VR1 was a comparable tire. I'm very interested to see how they do.
My favorite Enduro tire was the Rival and I'm sad it's no longer a thing. More grip than the others and lasted just long enough we could do a 14.5 hour race on 6.
In reply to Andy Hollis :
Know for the real test -R7 vs A055 vs new A005. And also Hoosier A7, A005 vs Pirelli Slick too! thanks Andy. I have friends that run the run the A7 to take an early lead in sprint racing with the other drivers in Pirelli's. I like your expanding testing to TT testing as well.
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