Bridgestone fills the gap between their road-biased Battlax A41 and aggressive AX41 with a tyre that can handle a bit of everything.
By design, adventure bikes are always a bit of a compromise. The premise of a motorcycle that can cover distances on tarseal to then ride off-road is always going to mean sacrifices are to be made. Comfort for the road often means less off-road prowess, while off-road ability usually equates to a sore butt and lack of performance on the road.
But the adventure market has exploded, with it undoubtedly being the fastest growing and most populous segment of bigger capacity two-wheeled machines. Back in the day, all manufacturers had multiple capacities of sportsbikes. Now, it’s not uncommon for one manufacturer to have adventure bikes ranging from small learner/LAMS varieties to monstrous 1200+cc thundering beasts. And that has led to an equal amount of development in the tyres to match these machines, with the same compromises riders find with the motorcycles never more evident than in the rubber they put on the wheels. Too much of an aggressive pattern to offer grip on the dirt means a noisy and unnerving experience on the black stuff, while road tyres in the dirt are never going to offer much confidence when trying to do your best Chris Birch impressions.
Tyre Technology
The burgeoning market has seen the tyre manufacturers throw as much attention into the adventure segment as they usually do making race bikes quicker around a circuit. Nowadays, there’s all sorts of new technology incorporated in the round rubber things we tend to think are all similar. But with the compounds and design of tyres making such a difference, it is no longer the case of knobs (or no knobs) when trying to pick what to put on your adv machine.
Bridgestone has been prolific in the adventure scene for many years, with their Battlax Adventure A41 the tyre you’ll find on many models when you pick them up from the showroom. Designed predominantly for use on the road, those looking for a tyre that’s more suited to a bit of rough stuff have either needed to switch to Bridgestone’s aggressive 50/50 Battlax Adventure cross AX41 or move to a different tyre brand. But now Bridgestone has developed a tyre to fill the gap, with the new Battlax Adventure Trail AT41 offering a chunkier look in an 80% road / 20% off-road package.
First and foremost, Bridgestone has developed the new tyre to work well on the road in varied conditions, with wet weather performance a prime focus in developing the new tyre. The newly designed tread pattern not only gives the tyres an aggressive ‘off-road’ look that most adventure bike owners crave, but the optimised grooves have been designed to improve water drainage. In fact, the amount of groove volume per revolution of the tyre is greater than the roady A41, which, combined with the dual compound rear and new compound for the front, actually gives the AT41 better wet weather performance.
The once-piece MS-Belt construction of the new tyres sees one single continuous strand wrapped around the circumference of the tyre, eliminating overlapping of belts, seams and joints, giving a lighter and more stable construction. This reduces heat build-up within the tyre and also offers high shock absorbing properties – everything you would ideally require with a tyre you’re going to take off-road. Plus, the addition of silica also adds to more wet weather performance. And while the block-shaped tread design is there to offer increased traction on loose surfaces, the trade-off is a slight reduction in dry road cornering grip when compared to the road-focused A41. By how much we were keen to find out, so after fitting a set to our longterm V-Strom 1050XT, I headed off for a 500km day from Hamilton to put the new hoops through their paces.
Looking Good
Picking the bike up from Boyds Motorcycles in Hamilton after having the new hoops spun onto the V-Strom’s spoked wheels, I was pleased with the more aggressive stance the AT41s gave the big Suzuki. I’ve put more aggressive knobblies on a V-Strom before, and while it was a blast being able to take the Strom to places you wouldn’t usually expect the big Suzuki to go, the trade-off was a reduction in road handling, a lot of tyre noise and regular visits to the tyre shop as they wore out quick. The new AT41s didn’t give the full ‘hardcore’ effect of the others, but they certainly gave the Suzuki a better look.
With a text from a mate saying he was catching up with the Thames Valley Ulysses group for a trip around the Coromandel loop, the plan was hatched to head over the plains from Hamilton early in the morning before joining the ride. Thankfully, the Pinlock visor system inside my Shoei Hornet adventure helmet meant I could shut the visor for some reprieve from the cold wind without steaming up inside as I clicked off the kays over the Hauraki Plains. Despite the knobbly look of the AT41s, there was no discernible noise from the tread pattern, at least that I could notice over the V-twin thrumb from the Suzuki’s Yoshi exhaust can. And giving the bars a waggle demonstrated they were willing to respond to inputs quickly.
Meeting up with 22 other riders who all had the same idea of joining in on a mid-week sunny loop of the Coromandel, the tyres received a few comments and squeezes from other adventure riders. With the majority of riders on adventure machines using them as comfortable tourers that come with the added benefit of letting you explore the roads less travelled, having tyres which can handle a bit of everything is an important facet, and the Bridgestones look to tick the boxes.
As we worked our way up towards Thames before hooking right and joining the glorious twistiness that is the Kopu-Hikuai road, I was gaining confidence in the new tyres as I joined the riders at the front who were pushing on. As the road winds its way along the side of the Kirikiri Stream before heading up into the hills, the corners get longer and faster before reaching the summit and dropping down the other side. Lots of the corners seem to go on endlessly, with confidence in your tyres making the difference between an enjoyable ride or a worrisome one.
Thankfully, the AT41s encouraged plenty of pace despite their block pattern, and even though the V-Strom is only pushing out around 100 horses, I’d be happy to run these hoops on the most powerful adventure bikes where there’s 150+hp attempting to overwhelm the rear tyre. As the speeds crept up, there still wasn’t any rumble or roar coming from the tread pattern, meaning they are going to be suitable for long-distance tours that include a bit of gravel or dirt along the way.
As the group headed up the eastern side of the peninsular and the corners tightened north of Whitianga, my confidence in the tyres had grown enough that I was carrying brakes into turns and powering out the other side, with all thoughts of the adventure style dispelled from my subconscious. Riding adventure bikes (especially powerful ones) with knobblies on is often an exercise in self-restraint, as it would be easy to find (and surpass) the limit of more off-road-focussed rubber. The Bridgestones didn’t find me holding anything back in reserve, even to the point of having to get my toes up on the pegs such was the level of lean achievable.
The Other Side
But riding on the road is only half (or should that be 80%) of the puzzle, so after lunch in Coromandel town, Tommo and I said goodbye to the rest of the group and found some gravel to explore. Okay, the 309 road that works its way east, back across the peninsula, doesn’t often feature rim-deep gravel. But the twists, turns and undulations of the dusty loose surface can easily catch you out. And while big block tyres are perfect for cutting through dirt and gaining traction in the loose structure underneath, the combination of deep grooves plus plenty of rubber was just right for this style of riding. And I’d imagine this is about as adventurous as many large adv riders are likely to get anyway.
The grooves on the front tyre did a good job offering more confidence under braking and cornering, certainly giving much more feel than if I was on the OEM Bridgestone Battlax A41s. Okay, if you’re going to be riding into mud or wet clay, then these ain’t the tyres for you. But as a tyre which will work well in a mixture of environments, the AT41s do the job. And the rear is even better, with the grooves going across the tyre hooking up on the loose surfaces and driving the V-Strom forward rather than spinning up and cutting in the traction control.
After heading up the road for a while, getting some photos, messing around and then deciding to turn back, the switch from dirt to road was seamless as the tyres offered plenty of confidence in both environments. With four different sizes for the front including a 90/90-21 and five for the rear for either 17-inch or 18-inch wheels, the range covers what you’ll require for the majority of big-capacity adventure bikes.
With the technology in tyres now so advanced, it’s no longer a case of just looking at the tread pattern and making the decision. It’s what’s in them and how they’re constructed which adds versatility, longevity and performance to these black round rubber things. Work out your needs, take account of your bike and how much you carry on it and then do your homework. For an adventure tyre that gives confidence on the road but can still handle some fun in the gravel, Bridgestone seems to have hit it out of the park with their new Battlex Adventure Trail AT41.
Article first published in issue 216 of Bike Rider Magazine
Bridgestone Battlax Adventure Trail AT41 Sizes
100/90-19M/C, 110/80R19M/C, 120/70R19M/C, 90/90-21M/C, 130/80R17M/C, 140/80R17MC, 150/70R17M/C, 170/60R17M/C, 150/70R18MC
For more details, visit www.bits4bikes.co.nz or visit your local motorcycle dealer.
