BONTRAGER XR4 TEAM ISSUE TLR TIRES

The missing piece of the puzzle

It is no secret that past tires from Bontrager, Trek Bike’s own accessory brand, are the reason Trek bikes have not scored higher in Mountain Bike Action shootouts. While reading between the lines was easy (just swap the tires and you’ve got a winner), this frustrated the crew in Madison, Wisconsin, so much so that they hired Frank Stacy (the most respected tire development guy in America, and maybe the world), to develop a tire line that would win bike shootouts for Trek. The $65 XR4 Team Issue TLR tire is the result of Frank’s labor.

Tech features: The XR4 Team Issue TLR tires are available in eight 26-inch versions (there is a separate 29er line), from our top-of-the-heap 26x2.20-inch Kevlar folding-bead tire to the $34 wire-bead version in a 2.35-inch width. The XR4 Team Issue TLR clincher model sports a directional knob pattern, dual-compound rubber and 120-threads-per-inch sidewall construction. The TLR means they can be run tubeless on the proper rim with sealant. The tire’s knobs have small grooves cut into them (called siping) to open them up for better ground contact. Our tires weighed 1 pound, 6 ounces each. You can reach Bontrager at (920) 478-2191.

Field test results: The first indication of major changes at Bontrager was that it was easy to mount the tires to our DT Swiss M1900 rims. With past Bontrager tires, the fit was inconsistent; some almost required motorcycle tire irons to mount them. Not these. The XR4 Team Issue TLR tires slipped onto our rims without tools. Two thumbs were all it took, and these were the TLR versions with added material in the bead. The non-TLR tires would be even easier to mount. The tires beaded easily to the rim (we used tubes), and we started out on the low side of the recommended air-pressure range of 30 psi to 50 psi with 32 psi in both tires.

The XR4s are intended for aggressive trail riding, but you could have fooled us with the way they pedaled. This is a fast-rolling, quiet tire. The tires damped trail minutiae (small rocks, loose gravel), giving the feeling of a cushioned ride. Although they rolled well, the tires offered plenty of bite under hard efforts and while braking. We couldn’t help but think that if they work this well with tubes, they will only get better without them. The biggest improvement was in cornering. There was a seamless transition from an upright riding position to cranking into a corner. There was no detectable transition from the center knobs to the shoulder knobs, which allowed test riders to trust the tires, get off the brakes and flow through the corners. The tires also proved to be durable and puncture-resistant. We put in plenty of miles on sharp rocks, goat-head thorns and glass-littered trails (shooters) without a problem. This is not only the best trailbike tire from Bontrager so far, it is a great trail- bike tire period. We predict you will see this Bontrager tire on bikes other than Treks. Yes, it is that good. It is a trail- bike tire that offers lots of cornering bite without charging a rolling-resistance tax. There is little doubt that the Treks equipped with the XR4 Team Issue TLRs are going to be finishing higher in future MBA shootouts.

 Reprinted from the January 2012 issue. Like us on Facebook