Are high-end sport-touring tires sticky enough for everyday canyon carving and an occasional trackday, or is it smarter to trade tire life for ultimate grip with race-bred street rubber?
We set out to answer this age-old, rubber-burning question with a long-term test of Bridgestone’s Battlax T30 EVO. For good measure, we then burned through a pair of similar tires from another top manufacturer, accumulating a total of 10,317 street and track miles while generating valuable comparative data.
[Although the T30 EVO has been superseded by the Battlax T31, we rarely get a chance to test matching sets of tires in such depth on the same bike. That’s where our detail-oriented friend of MO, Eric Putter, comes in. Sit back and enjoy his entertaining, data-heavy tale of tire-testing madness. – Ed.]
Whether through advances in molecular science and production processes, a combination of more sophisticated testing-sensor technology and analytics software, or feedback from actual human beings, the performance envelopes of sport and sport-touring tires have grown tremendously in the past decade.
Long-Term Testing in Our World
This pair of T30 EVOs was evaluated in the real world. Instead of carefully curated press-intro conditions in far-off lands, their proving ground was Southern California’s diverse landscape of mountains, deserts, and coastline.
Our testing regimen consisted of day-long canyon-carving missions mixed with overnight journeys on the sporty side of sport-touring and short hops slicing through LA’s notoriously snarled traffic, then topped off with a couple of track days. The Bridgestones were asked to perform in a dozen microclimates: Sea level to 7500 feet and temperatures from the mid-‘40s to the low triple digits. On tarmac that varied from clean, smooth, grippy, and dry to frost-heaved, tar-snake-infested, snotty, and rock-strewn. With and without tire warmers. This time, though, it was my bike, my roads, my tire pressures, and suspension settings.
The original T30 was introduced in 2014 to replace Bridgestone’s trusty BT-023. The EVO model is, yes, an update of its forebear. The EVO’s design brief mandated maintaining the T30’s exemplary dry-tarmac performance over a wider temperature range, then upping its game with new compounds and a rear tread design to greatly increase wet-weather traction.
That seemed a tall order, but get this: The first-gen T30 worked so well in damp conditions that it was adopted as the official tire of a riding school at Donington Park, a notoriously soggy British grand prix track.
Evolutionary – not revolutionary – updates to the T30 EVO were enough to earn it a new name. The current T31 was engineered to take another step toward sport-touring perfection, especially on wet pavement. It’s now Bridgestone’s top-of-the-food chain sport-touring tire.
On the way to better wet-pavement traction, the T30 EVO front tire evolved via a new chemical formulation for its single-compound structure. The dual-compound rear’s center section contains the latest generation of Bridgestone’s Silica Rich EX compound. Both were cooked up with the company’s exclusive NanoPro-Tech process that magically bonds a top-secret percentage of water-gripping silica to polymers that promote long tire life.
The EVO’s tread has groups of three, horizontally oriented, curved grooves around both sides of the tire’s circumference. To better channel water away from the contact patch, the trio’s middle grooves were much longer than on the original T30s. They were also closer to the center and extend further toward the edge.
To generate more sure-footed acceleration in all conditions, the rear EVO’s grooves were shifted outward to put more rubber on the road and simultaneously create a stiffer center tread for more stability when applying horsepower to tarmac. This, said Bridgestone, also increased the contact patch as a bike leaned into corners. Less tire spinning and more edge grip? We’ll take it!
Outside the lab, Bridgestone test riders were 9% faster on a wet-handling course with the EVOs than original T30s, satisfying the science geeks and engineers. Mission accomplished!
The Right Tool for the Job
To accomplish our mission, we needed the right tool for the job. It seems as if the EVOs were designed specifically for this ergonomically modified 2007 GSX-R1000 supersport-tourer. It’s a genre-melding, half-faired hybrid that offers upright, naked-bike comfort in a lighter, faster, better-suspended, sharper-handling package than a Yamaha MT-10 or Suzuki Gixxus 1000.
This GSX-R’s rider triangle was expanded with a beefy, aftermarket upper triple clamp topped with risers holding a Renthal handlebar, complemented by micro-adjustable, billet aluminum ASV Inventions C5 clutch and brake levers and 1-inch-lower footpegs bolted into the Suzuki’s stock rearsets, which were set in their lowest, farthest-forward position. A taller Zero Gravity Touring windscreen and comfy Latigo seat complete the package. For about 500 bucks most motorcycles can be transformed with just a triple clamp, Superbike-style bar, and longer control cables (or hoses).
The result is 19.25 inches of legroom and a 26.5-inch reach from the seat to the 6.5-inch higher handlebar – ergo dimensions that are much closer to those of the FZ-10 and GSX-S1000 than bare-knuckled Euro streetfighters from Aprilia, BMW, and KTM.
Because the Gixxer’s stock stable of ponies wasn’t enough to properly stress the T30 EVOs, in the name of science (wink, wink, nod, nod) we subjected them to even more stupid-fast, tire-shredding power with bolt-ons from Brock’s Performance. A full exhaust system, custom-mapped Power Commander, Sprint Filters air filter, and some secret sauce poured in the crankcase easily put the high-mileage, long-stroke motor on level with today’s superest superbike engines.
Street and Track on the Same Tires – On the Same Day?
As cowboys say, this wasn’t my first rodeo. Yeah, I’m that guy. The crazy Californian who leaves at ‘o-dark-30 to endure an hour-long freeway drone on a trackday-prepped, fresh-tired sportbike, hits Angeles Crest Highway at dawn, does 60 miles of twisties followed by a high-speed desert crossing, pounds out a day’s worth of hot laps at Willow Springs Raceway, then retraces the raucous route home.
I’ve also been the hardcore New Yorker on a sport-touring-tire-shod naked bike who suffers through 160 miles of industrial stench and pothole-ridden highways in the wee hours of the morning for the privilege of playing trackday coach and cop at New Jersey Motorsports Park. Then, 150 miles later, points the street-and-tracksickle north for the journey home. Yeah, really, that guy.
Prior to the T30 EVOs, our test mule wore Battlax BT-016 Pros, bought when the company was offering $50 cash back on each. (You can check for current rebates at the Bridgestone Rewards Center.) The 016 Pros lived a harsh life on the street and at a trackday, holding up well for 3,853 miles. Your tire-melting mileage may vary.
For years, GSX-R1000s came from Suzuki equipped with OEM-spec Battlax S20s, in 120/70 and 190/50 sizes. We chose the T30 EVO radials in 120/70 and 190/55 sizes. Specifically, a 120/70ZR17 M/C (58W) TL front and 190/50ZR17 M/C(73W)TL rear for the 3.5 and 6.0 rims. Stamped with their “W” in parentheses, the highest speed rating: more than 168 mph.
Bridgestone now has six Battlax sport and sport-touring tire choices for our test subject. The slick-like Racing Street RS10, Hypersport S22 and S21 street & track skins are biased more toward the sporting side. The T31, T30 EVO and BT-023 more geared to sport touring.
To accommodate aggressive sport-touring riders on traditional big rigs such as the BMW R1200RT, Kawasaki Concours and Yamaha FJR1300 – motorcycles that are 30 percent heavier, before luggage and passengers are taken into account – Bridgestone offers GT-spec T31s T30 EVOs and BT-023s. .
The front GT’s plies are angled to stiffen their carcasses, and the tires’ tread patterns were modified. The rear carcasses are wrapped with an extra belt to strengthen their construction. The upgraded tires are said to deliver the same handling characteristics as the standard tires on these big rigs.
Dollars & Sense
The tire market is super-competitive. Usually, most big, online retailers’ prices are within a few dollars of one another on popular tire brands’ latest models.
This time, RevZilla won the dollars & sense battle. For $260.32 (after figuring in our 7.75% local sales tax and cashing in on Bridgestone’s $50 promotional rebate) , including free shipping, we could have purchased this set of T30 EVOs had we not gotten them directly from Bridgestone for testing. A quick check of RevZilla’s pricing just prior to publication revealed that pre-tax costs of the latest high-end sport-touring tires in 120/70 and 190/55 sizes varied by just $37.63:
- Bridgestone T31: $335.44
- Dunlop Road Smart 3: $322.35
- Michelin Road 5: $351.97
- Pirelli Angel GT II: $359.98
Compare this to the companies’ current street & track skins in the same sizes, which average out to be $12.58 less per set:
- Bridgestone S22: $360.94
- Dunlop Q3+: $319.65
- Michelin Power 2CT: $274.86
- Pirelli Diablo Rosso Corse II: $363.98
Like all tire companies, Bridgestone suggests street-tire buyers follow manufacturer-recommended settings for their bikes. For 2007, Suzuki equipped U.S.-bound GSX-R1000s with Bridgestone BT015 tires, aired up to 36 and 42 pounds, front/rear.
Ever the traction-greedy rebel, I proactively adjust tire inflation and suspension settings to suit each day’s mission, luggage and passenger loads. In most cases, this is a few pounds shy of an OEMs’ safety zone.
A Weighty Situation
Believe it or not, most sport-touring tires are very close in weight to their street- and track-focused brethren; fronts within a few ounces and rears about two pounds heavier.
In this case, at 9.6 and 15.5 pounds, respectively, the 120/70 T30 EVO front is actually 1/10 pound lighter than an identically sized Bridgestone RS10 trackday tire, but the 190/55 T30 EVO rear is 1.8 pounds (13.1 %) heavier. A comparable, heavy-duty EVO GT rear tire weighs just 8 ounces more than the standard version.
A Year in the Life – Rolling Road Review
Call me a simpleton, but I’m basically happy if the tires on my bike are black, round, and sticky. The road to nirvana includes quick, consistent warmup, good bump absorption, neutral handling characteristics, and secure braking grip. The best-case scenario is when they also keep the bike’s rear end from stepping out under reasonable throttle inputs and from sliding due to a mix of trail-braking and cornering forces.
Testing Report #1
Cumulative Miles: 0 to 1561
Report Total: 1561 mi.
Street Use: 1561 mi.
It’s now time to see if the T30 EVOs land in the happy, happier, or happiest column.
Proudly stamped “Made in Japan,” both tires were manufactured just two months before being mounted, when the GSX-R’s odometer registered 23,739 miles. Other than relatively tired stock suspension components, the bike had a clean bill of health.
After heeding Bridgestone’s scary-sounding, yet common-sense break-in recommendations – Avoid sudden acceleration, maximum braking and hard cornering for the first 100 miles – we proceeded to rack up another 1461 relatively sedate, drama-free miles during the initial third of this test.
Still haunted by visions of riding a first-gen GSX-R1000 test bike down my apartment complex’s short, steep final transition to the roadway, unweighting the rear wheel, spastically spinning a donut with a small dose of throttle, and unceremoniously crashing on cold tires, the T30 EVOs were treated with kid gloves for the first 300 yards of every outing. Relative to air and pavement temps, on the street, they warmed up predictably within a mile.
During this initial test period, the Bridgestones proved grippy and communicated confidence-inspiring feedback in all scenarios. Even during spirited sorties on tight, bumpy and sometimes dirty coastal canyon roads, at speeds between 20 mph and the middle of second gear, the EVOs consistently held up their end of the bargain.
They also took to the fast sweeping corners of our beloved-yet-frost-heaved Angeles Crest Highway. With elevation rising 6700 feet in 45 miles and a temperature difference of 20 degrees from bottom to top, its grip was generous and consistent until encountering slip-inducing tar snakes. Thankfully, traction reliably returned milliseconds later.
Tire Wear: 0 to 1561 miles
In its first 1561 miles, the T30 EVO front averaged just .2 mm of wear across its tread from an original tire depth (OTD) of 3.97mm. The rear tire’s 6.35mm OTD was melted away by an average of 1.73mm across the tread. Considering the legal tread-depth limit of 1.59mm (.063, 2/32 or 1/16 of an inch), this was 8.4% of the front tire’s usable life and 36% of the rear’s active duty.
During this time, the T30 EVOs steadily held air pressure – in heavy use and during riding lulls – and looked none the worse for wear.
Testing Report #2
Cumulative Miles: 1562 to 4061
Report #2 Total: 2499 mi.
Street Use: 2351 mi.
Track Use: 148 mi.
Street Handling, Ride and Braking
The second phase of tire testing commenced after our test subject received suspension upgrades from Lindemann Engineering that made the next 2500 miles much more exciting. Even with new springs and revalved damping magnifying the EVO’s handling, ride and braking qualities, the ‘Stone-shod GSX-R lost none of its sporting feel and performance capabilities during all-around street use. The T30s gave it neutral and balanced steering, predictable turn-in manners, and great stability at all lean angles – from edge to edge. More effective damping and the sport-touring tires’ carcasses teamed up to provide a better ride than ever.
The T30’s more forgiving structure didn’t adversely affect braking stability. The front multi-tasked well, producing great, straight-up grip and minimal stand-up on the brakes when bending into corners, even while delicately trail-braking up to their apexes. Not as effortlessly powerful as modern systems, this Suzuki’s generations-old stopping hardware, complemented by a one-piece, steel-braided Goodridge Superbike brake lines, and EBC HH brake pads, provided great feel for diminishing traction as the tire communicated varying grip levels.
MotoGP gods with superhuman feel for traction can dance on the edge and win races in sketchy weather conditions. For most mere mortals there’s no joy in wet-weather street riding.
That said, after surviving hardcore electric vest tests on moonless winter nights at 8000 feet, what’s a little rain? So, with a fresh Nikwax waterproofing treatment on my trusty Aerostich Roadcrafter, I sporadically braved some nasty elements and was caught out by showers on several occasions but didn’t suffer through full-on rainstorms.
Tip-toeing around the mean, wet streets of LA, navigating canyon roads overcome by coastal fog, and dodging California freeway drivers mentally-paralyzed by water falling from the sky, the EVOs provided predictable handling and confidence-inspiring traction, just less of each in every situation.
Dry Lab Sessions
Here in California, racetrack outings are more akin to dry lab sessions than controlled chaos on wet tarmac. At the 2000-mile mark, these sport-touring tires faced their toughest test yet: A near-midlife crisis that lasted 148 hellish miles averaging 83 mph in 80-degree weather on my home track, Auto Club Speedway’s 2.36-mile road course, during a Fastrack Riders track day.
Fast Track Lab
Just east of Los Angeles, the superspeedway’s banked oval sucks NASCAR Cup race cars into the tarmac, helping drivers average nearly 200 mph around the two-mile-long, D-shaped track. Bikes run exclusively on Auto Club’s relatively flat, 20-turn configuration within the oval. Utilizing much of the main track’s 3100-foot, 11-degree-banked front straight, it has a good mix of fast turns, tight, tricky corners, hard-braking zones, and wide-open-throttle sections where the T30 EVO’s performance limits could easily be found and comfortably pushed.
During a typical lap at Auto Club, we were accelerating more than half the time, topping out at around a buck-sixty before scrubbing off speed and tipping into the first turn’s Mickey-Mouse chicane at 100+ mph. G-forces generated on the banking and the multitasking undertaken through 15 left-hand turns abused the tires’ left shoulders, while their opposite sides naturally cooled down before being flicked into tight right-handers spaced far apart.
Although conventional wisdom says that street tires don’t need warmers during trackday use, for peace of mind and to make the most of every 20-minute session, Chicken Hawk Racing’s dual-temp warmers were mounted.
“Even on the track, 90% of riders would be better off on street tires,” insisted World Endurance Champion, AMA 750 Supersport title holder and championship-winning rider coach, Jason Pridmore. “This is because street tires warm up faster,” he continued, “and won’t drop below their operating temperature at lower speeds. The compounds they’re made of are meant to heat cycle often without ill effect, while those track tires will be spent after just a few uses, leaving you with hard, unsafe tires in a very short amount of time.”
Heeding Pridmore’s advice, we also went out on cold tires. And he was right: The T30EVOs built confidence-inspiring traction in just one lap. Whether they need it or not, I give trackday tires and full-on slicks an extra warmup lap if they weren’t preheated to 180 degrees in electric blankets between sessions.
With or without warmers, in less than an hour’s worth of track time on the 1000’s cushy seat, this relatively heavy, softly sprung, high-barred, sport-touring-tired steed and I were comfortably laying down lap times within 2.6 seconds (or 2.5%) of those posted a month earlier on my usual ride, a hypersport street & track-tire-equipped GSX-R750.
Ironically, the official motorcycle lap record at Auto Club Speedway – a smokin’ 1:22.404 by World and AMA Superbike Champion Ben Spies – was laid down by another 2007 GSX-R1000. While I’m certainly no factory rider and the comfy Gixxer isn’t quite as super as Spies’ ride, my lap times at ACS are generally in the upper third of intermediate-level group or the lower third in advanced-level sessions.
In an effort to compare the T30 EVO’s track performance to race tires in similar conditions, for the next Fastrack event at ACS, a fresh set of slicks were mounted, the motocross-style handlebar was swapped for a set of HeliBars’ TracStar clip-ons, and the bike was ridden 60 miles to Fontana on its trackday suspension settings.
In this guise, the 1000 took me to a personal-best lap time almost five seconds (or 5%) faster than when set up for everyday riding. The downside is that the rear slick was exhausted in just 649 miles. This worked out to five track days and 120 freeway miles during a dozen heat cycles.
|Lapping Auto Club Speedway: Author’s Best Lap Times|
|2007 GSX-R1000 on T30 EVOs with ergo mods: 1:48.003|
|2011 GSX-R750 (bone-stock) on Dunlop Q3s: 1:45.382|
|2007 GSX-R1000 on Dunlop slicks with HeliBars and stock footpegs: 1:43.274|
|Official motorcycle lap record: Ben Spies: 1:22.404|
Tire Wear: 1562 to 4061 miles
Even while approaching the end of their lives, once back on the street, the aired-up EVOs didn’t feel worse for the punishment they received in Fontana, and their shoulders proudly wore telltale signs of track use.
After another 2499 miles, a second round of tread measuring revealed that the front Bridgestone averaged .76mm of wear across its tread, and the was rear melted away by an average of 1.78mm. Considering their cumulative wear totals of .96mm and 3.51mm after 4061 miles, the front was just 40% into its life; the rear nearly twice that, at 74%.
Testing Report #3
Cumulative Tire Miles: 4062 to 4559
Report Total: 497 mi.
Street Use: 359 mi.
Track Use: 138 mi.
Visiting Hill Country
Chauffeured eight hours in a pickup truck headed north, the big Gixxer put its EVOs to their final tests. Our first stop was at the beautiful, undulating Sonoma Raceway, in you guessed it, California’s fabled wine country.
Although it’s also hosted NASCAR, this hillside track couldn’t be any more different than the afterthought of a roadcourse inside Auto Club’s superspeedway. Best known as Sears Point, then Infineon, after a corporate buyout, the now aptly-named track has a 2.52-mile motorcycle track configuration that flows up, down and around rolling hills with 160 feet of elevation changes. It has 12 corners with 16 direction changes — six left-handers and ten rights.
I’d attended and photographed races at this historic venue, but never put tire to tarmac. During this track day, we covered 138 miles. Even when using less lean angle than normal, with or without tire-warmer preparation, the EVOs’ limitations became easier to find as they approached the end of their usable lives. While being quite respectful of this, we certainly didn’t tip-toe around. Losing none of their ride quality, the ‘Stones continued to dole out and absorb tremendous acceleration, cornering and braking loads. In fact, the front tire still gripped tenaciously enough to lift the rear wheel under hard braking from triple-digit speeds.
The T30EVO’s last day transferring power, carving corners and hauling the GSX-R down from speed was spent careening around wine-country roads. Even at the 4200-mile mark, their performance wasn’t fading. Ride quality was still excellent. They continued to provide the consistent traction and feedback needed to safely traverse the area’s sometimes moist and dirty roads.
A weekend at the racetrack and romping around wine country was a fine way to end this happy relationship at 4559 miles. Again, your tire-melting mileage may vary.
Could more miles have been squeezed out of the EVOs by running higher tire pressures, not being so greedy with the GSX-R’s throttle, trail-braking up to corner apexes or accelerating out of them while leaned over, or (gasp!) steering clear of racetracks altogether? Yes, but we were having none of that. Sure, tire purchases are made using an equation that divides cost by traction + tread life. As always, the above-described shenanigans were well worth the reduced return on mileage.
Thankfully, this was a real-world evaluation of the EVO’s traction, handling and wear characteristics, not a high-mileage contest or tire shootout. The hard data gleaned in 4559 miles provided a basis for comparison to tires mounted on this bike immediately before and after the T30 EVOs – all with the same rider on many of the same roads and tracks, in similar conditions.
Tire Wear: 4062 to 4559 miles
In their final 497 miles the EVOs’ wear greatly accelerated, by up to 17% on the rear’s left side and middle, but as mentioned above, their performance didn’t drop off as dramatically.
After 4559 miles, the tires’ wear patterns clearly documented my riding style: Generous applications of trail braking, using less mid-corner lean angle than the contact patches made available and standing the bike up before accelerating, their extreme edges registered the least wear. Much of the flanks’ rubber was shed just past the danger zone, which, clearly, is my happy place. The treads’ center sections landed at opposite ends of the spectrum: Up front, just 34% of the total tread depth wore away; out back, the wear bars were showing because 76% of the rubber was gone in some spots.
To establish a firm basis of comparison with a similar sport-touring tire immediately after the T30’s successful tenure ended, a pair of Michelin Pilot Road 4s were spooned on the GSX-R1000’s rims. They went 5758 miles in similar conditions on many of the same roads.
Cost Per Mile
The penny-pinching contest was nearly a tossup. The $260.32, 4559-mile T30 EVOs cost just 5.7 cents per mile. Although the Michelin Pilot Road 4s lasted an additional 1200 miles in similar street conditions (yet 56 fewer track miles), at $342.64 per set, they ended up costing .2 cents more per mile to run.
The T30 EVOs shed more than four pounds of rubber in 4559 miles. The 190/55 rear tire went from 15.5 when new to 12.4, a 20% change. The 9.6-pound 120/70 front skin lost 1.2 pounds, making it 12.5% lighter at the conclusion of testing. So, yes, theoretically, as their tires wear, motorcycles can handle better and have more compliant suspension due to carrying less unsprung weight.
|Front: 120/70 x 17
New: 9.6 lbs.
4559 miles: 8.4 lbs.
Loss: 1.2 lbs., 12.5%
|Rear: 190/55 x 17
New: 15.5 lbs.
4559 miles: 12.4 lbs.
Loss: 3.1 lbs. 20%
In the big picture, these Battlaxes lived a typical life on my primary form of two-wheeled transportation and entertainment. They held up well, never suffered a puncture, and their 4-year limited warranty (before a tread depth of 1/32 of an inch) wasn’t called upon.
Livin’ The Life
Bridgestone recommends the T30 EVOs “for riders who enjoy riding a super sports bike with touring tires” and “…who want to safely ride even if caught in a sudden rain shower.” Years ago, I wouldn’t have been caught dead riding a sportbike with touring tires for fear of, well, being caught dead. Even if I was caught in a sudden rain shower. Even while sport-touring on a sportbike.
Starting this long-term test with a set of Battlax T30 EVOs, then wearing out comparable Michelins, I’m terribly impressed. After more than 10,000 miles of testing, it’s fair to say that today’s sport-touring tires are great for commuting, sporting forays, and yes, an occasional track day – even on an aggressively ridden sport-touring superbike.
In fact, the latest trackday, street and sport-touring tires from top companies are pretty damn good overall. Like today’s motorcycles, modern tires’ capabilities exceed the performance needs of their applications and demands of most users. Sure, each have distinct characteristics and nuances specific to their intended use, cost considerations, design philosophy, and DNA, but very few are true duds.
Because most riders don’t have the luxury of owning two motorcycles or two pairs of wheels for their sportbike, I’ll continue recommending the latest sport-touring rubber over flashier, nearly-treadless-yet-stickier hypersport street & trackday skins everyday riding .
So, are Bridgestone’s Battlax T30 EVO, the T31 that superseded it and similar products from other top manufacturers: A) Sport-touring tires for sportbikes or B) Sport tires for sport-touring bikes? This trick question resulted in two affirmatives contained in one word. The answer is, you guessed it: Both.
Eric Putter is a veteran journalist who believes in science. He’s tested moto-related products for decades, toured on sportbikes shod with trackday skins, ridden racetracks on sport-touring tires, and visa-versa – sometimes in the same day.