Tire selection is a very personal choice. Bontrager understands that. The company’s website says, “The first step in finding the right tire is deciding how much tread you need.” That’s solid advice. I find that few components choices are more personal than tires.
Bontrager classifies its tires on a 0 to 5 scale (plus a mud-specific tire), with lower numbers indicating “lighter, fast-rolling treads best suited for hard-pack courses.” Tires with higher numbers have progressively larger knobs that enhance traction in loose terrain and wet conditions. Aggressive treads offer better traction, but with improved grip come the tradeoffs of increased rolling resistance and heftier weight.
When looking for 29plus rubber for summer conditions, I snapped up a pair of Bontrager XR2 Team Issue tires in 2.6 width from the product shelf at Dirt Rag HQ. The included diagram from Bontrager supports my choosing the XR2s, as their strong points match my local conditions during the typically dry summer season.
Nick Anger, my product contact at Bontrager said: “The XR2 is the first tire in the lineup that you’d jump to as soon as you’re no longer solely riding in dry and hardpack conditions, and riding more in a variety of hardpack/loose/loamy conditions … As XC World Cups get more and more rugged, you see Trek Factory riders rely on this tire more and more. The XR2 provides a great balance of traction and confidence with fast rolling and lightweight, especially in larger sizes.”
Anger went on to say that renown tire designer Frank Stacey helped develop the tread pattern. If the name Frank Stacy is news to you, check his website to learn more about his tire design and testing chops.
Before I get to my ride impressions, I should mention that tires with the “Team Issue” designation include several key features: aramid bead, 120 TPI casing, tubeless compatibility and “Inner Strength” sidewall protection.
Tipping the Dirt Rag scale at 760 grams, the XR2s felt fast for 29plus tires. There was very little audible “buzz,” which helped my brain convince my legs that these tires roll with minimal resistance.
After spending a few rides getting used to the XR2s, I grew to trust the tires and didn’t have to think much about them. I received clear communication from the tires’ contact patches, so I always felt like I knew what was going on at ground zero.
While the XR2’s tread may appear diminutive, eight rows of well-siped knobs spread across the tire’s 2.6-inch girth hooked up securely on hard-packed, loamy and loose-over-hard surfaces. The supple 120 TPI casing and the ability to run low tire pressures (tubeless) helped the tires conform to uneven surfaces and provided reliable, predictable grip. The looser/rockier the surface the less secure the tires felt, which is pretty much as advertised.
Lacking aggressive knobbies, the XR2s were overmatched in seriously muddy conditions. Again, as expected. The ample siping on the knobs seemed to help them bite on damp surfaces, and the XR2s did a decent job sticking to sweaty rocks and holding on to slimy roots. No need to fret over a stray shower or an occasional wet spot.
“Getting my lean on” was the most advisable method for maintaining traction in fast corners. The rounded tire profile and relatively uniform knob pattern kept the XR2s feeling consistent as I leaned deeper and deeper onto their broad shoulders. Coming in hot with a too-upright posture is poor cornering technique, and whenever I forgot that fact, drifting tires refreshed my memory.
Previous experiences with more-aggressive 29plus tires often left me feeling like I had “too much” tire for the trails that I ride most of the time. I’m happy that I decided to run the XR2s this summer. They’re fast and fun. I’d even say race-worthy. If you spend most of your time riding on maintained trails, rather that scouting sketchy backcountry routes, the XR2 Team Issue tires should be right up your alley. For looser or wetter conditions, I could see leaving the XR2 on the rear and running a front tire that ratchets up the traction by a notch or two.
The 29er XR2 Team Issue is available in 2.0, 2.2, 2.35, 2.6 and 3.0 widths; the 27.5 size comes in 2.2, 2.6 and 2.8 width. There’s even a 26 version in 2.2 width. Prices vary depending upon the width: 2.0-2.35 width = $55; 2.6 width = $65 and 2.8-3.0 width = $95. XR2s are also available in less-expensive Comp models. More at: trekbikes.com