Rennie Scaysbrook | May 23, 2018
Battling Out The Miles
Bridgestone’s T30 Evo sport touring tire has been demoted. Meet the Japanese rubber giant’s new baby—the Battlax T31
Banking the Super Duke GT in. The Bridgestone T31’s have excellent steering response and braking stability.
If you own a modern sport-touring motorcycle, you’re pretty damn spoiled for choice these days when it comes to the black things that cover your wheels. Tires are getting stickier yet are able to disperse more water, meaning riders with sport-touring bikes are not that far behind their sport-bike brothers and sisters in terms of overall performance.
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By Rennie Scaysbrook | Photography by Bridgestone
Bridgestone has been fending off hard challenges to sport touring dominance from guys like Pirelli, Dunlop and most recently Michelin with their recently released Road 5, and it’s been three years since the release of the Bridgestone Battlax Touring T30 Evo, itself an updated version of the T30 with better wet-weather performance.
There’s now a whopping 22 sizes available for the T31 with five GT sizes specifically for high–power, high-weight bikes. The T31 now sits atop the sport-touring pile for Bridgestone, with the T30 Evo moved down the pecking order to second, and the BT-023 third. The T30/T31 series is the most touring-focused of the Bridgestone range, meaning if you want more performance with less of an emphasis on wet-weather ability, you might want to look at the S21 we tested a few years back in Abu Dhabi.
There are 22 different sizes of T31 available now, including five GT-spec tires.
Selective Breeding
Taking the best points of the T30 Evo, the T31 aims to give more feedback to the rider in cold and wet conditions, more grip under heavy-braking loads and full lean, an increase in camber thrust so you can take corners faster with more grip, better straight-line and high-speed stability and no increase in tire wear. I guess if you get all those points spot on, you’ve hit the holy grail.
“In terms of tire development, it’s complicated,” says Fabian Francois, head of Field and Product Planning Engineering for Bridgestone Motorcycle tires. “In this category, we have to fit a large range of bikes—everything from bikes with 60 horsepower through to heavy naked bikes like the S 1000 R and Super Duke GT—these bikes must all have one tire.
“The T31 is a completely new tire for us. The pattern design is completely new, same with the compound. The construction is similar but revised compared to the T30 Evo.”
Bridgestone’s Monospiral Belt Construction sits beneath an all-new tread design.
The front T31 uses Bridgestone’s mono-compound construction, with much development attention devoted to the rubber silica molecules and how they conform to the road surface.
“The front T31 tire has much more flexibility compared to the T30,” says Francois. “We achieved that by increasing the silica dispersion. Silica is one of the components we are using in our rubber for working in lower temperatures and wet conditions, to generate good, repeatable performance. With the higher flexibility comes better feeling on the road, and more feedback to the rider.”
Using the company’s Ultimate Eye technology that was first used on the S21 in 2016 (Ultimate Eye is basically a rolling tire dyno), the new T31 shows it’s got a bigger adhesion and smaller slip area, which gives the double barrel win of better wet cornering grip and faster response time in the dry. The contact patch is up seven percent over the T30 Evo from 0° to full lean, and more tire on the ground means you can hit the upcoming corner faster and safer.
In regards to the wet-weather performance (one we didn’t get to explore on our test), the land/sea ratio in the shoulder has been increased to disperse more water, while the ratio has been slightly decreased in the center.
More water dispersion is one of the main aims with the new tread.
On the rear, Bridgestone has used their 3LC compound design, whereby the harder center compound runs underneath the two softer side compounds to add some extra rigidity under high cornering loads. Having the dual compound thus aids longevity, as well as high-speed stability. Although this is only a feature of the rear-tire compound, not the front, as is the case, some of the Adventure A41 rubber we also rode at this test.
Into The Desert
Just like we did the Adventure A41 a few weeks ago, the T31 was tested around the swirling valleys of mysterious Morocco, a land I never thought I’d experience and will be forever thankful that I did.
But there was one issue with riding in Morocco, and that was the lack of a wet-weather testing, so for you guys who live and ride in predominantly wet conditions, I’m sorry, but I’m none the wiser as to the T31’s performance gain.
As for general riding, though, the T31 performed admirably on the often dusty and slippery road surfaces we encountered on the test. Personally, my two biggest tests for any road-based tire revolve around braking stability and initial turning response, and the T31 handled both areas extremely well.
Where the tire was especially impressive was when I overcooked a few tight corners and could dial in more brake, then pull the bike back on line easily. Here, the Bridgestone engineers have succeeded in giving excellent feel back to the rider, so you know exactly what the tire is doing at all times.
Under brakes and through the initial stages of turning, the T31 gave smooth and predictable steering response, although I wasn’t prepared to really get the Super Duke GT cranked right over due to the dust storms that often flooded the road, so I can’t comment on edge of the tire grip.
Morocco certainly can throw up the scenery!
The rear tire was likewise impressive, with a huge amount of acceleration grip and stability. The Super Duke GT is one of the most powerful sport-touring bikes on the market, so the stresses put through the T31 were not inconsiderable, but the Bridgestone handled everything I could throw at it over a 180-mile day.
For a short day in the saddle, the T31 performed brilliantly, although I’d like to get these on a long-term test bike to test the wet performance and the overall longevity of Bridgestone’s latest touring hoops. CN
Here’s the video from Morocco where we took a quick spin on the new Bridgestone Battlax Touring T31and Adventure A41 tires:
Bridgestone Battlax T31 and A41 Tire Review
