Bontrager RSL Trail Handlebar-Stem

Keith Bontrager

There was a time where innovation came from within all the holes of the mountain biking industry. The year was 1978 and there were some hungry Californians trying to make shitty bike parts better for off-road use. Around that time Keith Bontrager was also cutting up 700c road wheels to re-roll them to fit 26" mountain bikes. Bontrager's self-sufficiency meant that he could experiment with different materials and production methods to streamline and increase product strength at the same time.

Keith set up testing parameters and procedures to study the effects of TIG welding on tubes. There was a constant strive to find flaws and improve on them. He knew that bike parts could be lighter and more durable. Trek saw the potential in him and his testing procedures. The Bontrager name was purchased in 1993 and Keith was hired to run production at Trek's Waterloo Factory. Bontrager became a TREK house brand in the 90s, but it was also a testing and innovation hub for the brand. A great way to test new technologies without attaching Trek's name on them gave the Bontrager line the freedom to do some crazy things with materials.

Bontrager Race Shop Limited MTB handlebar/stem

The Bontrager name lives on Trek bikes as handlebars, stems, wheels, droppers , etc quite successfully. The componentry can be found readily on everything from $500 city hybrids to $16,000 super bikes. Although the quality, fit & finish, and purpose of those parts differ, there is very little done to the branding to distinguish the low from the high-end. The RSL series fills that gap nicely as the high-end option on mountain and road bikes.

Right around the same time Keith was working on pretzeling perfectly good road rims, Tom Richey and Charlie Kelly were working on a stem that wouldn't let the bars slip from its grip on rough descents. Anything available at that time had too much leverage and not enough clamping power. So they went ahead and welded 2 quill stems to a steel cruiser bar, then called it the Richey Bullmoose. The Bullmoose was the first once-piece mountain bike handlebar stem combo on the market and was still somewhat available until about 4 years ago as a Carbon XC product.

Scott came up with the Syncros Hixon bar, and Gemini Components (former UNNO employees) are making slick one-piece bars in Barcelona. The demand for space-age cockpits is here.

Trek has done their research. With the human power they have at their disposal and all the data they have access to, it is no surprise that this product came out of the molds as they intended it to. I received the Trail Version of the bars at 820mm wide and 35mm stem length. The bars were cut to 780 as soon as possible after I weighed them on the scale.

The backsweep is 7° and upsweep is 6°. Just about where I enjoy my bars at in traditional ways. Sweep geometry was similar to my daily driver Chromag OSX 31.8 bars, which made the switch extremely familiar and uneventful. Going up to 27.5 mm rise from 25 meant that I would drop a small spacer from the steerer to keep the stack height consistent. A 5mm shorter stem length difference did not bother me on the first ride, although I had initially asked for 45mm option which was not available at the time.

The aesthetics of the combo looked right at home on my Forbidden Druid as the lines of the bars matched of the bikes perfectly. It may look a little out of place on a full metal welded bike.

Having some experience with the Syncros Hixon one-piece bar stem combo, I was braced for a harsh ride on this ultra slick and stiff looking setup. I find the Hixon bar to be less forgiving than the aluminum ones on my bikes. I dropped in to the first descend with a little caution hoping I had remembered to tighten all the bolts I loosed on the swap. The difference to the feel of the front end of the bike was immediately noticeable. A muted, comfortable ride was on the platter and steering felt fast, precise and familiar. My hands seemed to be in the position I am most comfortable with on my traditional Chromag bars with Deity stem combo.

After that successful first ride, I came home to "feel" the flex on the bars in the bike garage:

• Chromag OSX 31.8
• Race Face Next R
• Spank Vibracore Spoon 35mm
• Syncros OEM 31.8 alloy

The flex I could generate with my fingers on the stationary bikes was obvious. The Bontrager RSL bars flexed visibly the most, followed by the Syncros OEM bars, followed by the Spank, and finally the RaceFace Next R being the stiffest. All these bars are attached to bikes hanging on the wall. So the flex I observed was not pushing down on the suspension, but bending back as you would do to snap a twig to start a camp fire.

Yes! Very scientific I know, but I hoped Trek had done their homework on the comfort, while leaving the riding and the experience advising to me. Being an occasional hack, I managed to put a few dents in the ol' body of mine over the years. The multiple broken wrists and separated shoulders do not like overly stiff setups for anything short of a full on race. I will take engineered compliance in my touch points wherever I can. These Bontrager bars felt positively soft without being wet noodles.

Although I don't weigh my bikes that often (dreams do get crushed on the scales) I do own a digital scale where I measure to see if I was served the equal amounts of pasta on my lady's plate, every so often. I tossed the Chromag OSX 31.8 and Deity 40mm Copperhead stem on to the scale for starting point: 463 grams.

The RSL Handlebar combo was next on the dinner equalizer (kitchen scale): it read 268grams. The 200-gram weight savings was appreciated on the 34.5-lb Druid. I can't say I've noticed this change in riding weight but I will gladly take the psychological boost.

There are 2 shims included with the kit to fit Trek bikes or any other bike. As the trek knock-block headset has notches to lock into the stem, one must use the corresponding stem shim that fits into a slot in the clamp. I used the simpler, non-knockblock shim to fit on my FSA headset. The aluminum shim I believe increases the stem clamping forces as I find some carbon only stems tend to slip on the aluminium fork steerers unless over-torqued. The Bontrager RSL combo tightened to 5.2Nm smoothly and stayed slip-free since the day of the installation. Congrats for doing what you are supposed to!

If you don't roll your bars forward or backwards for any particular reason, I imagine you'd enjoy the feel of these bars and the geo numbers they are built to. The trail chatter is muted through OCLV Carbon layup.

There is also the super cool looks that you can get behind. If you are wondering how you are going to run your Garmin or night-time riding lights, there is a mounting hole with an aluminum insert on the front that will take numerous Bontrager Blendr light or GoPro mounts. The bars didn't come with one but any Trek dealer will be able to get you the $5 mount so you can run gadgets on the bars in the most integrated way possible. Hey, it's a threaded 4mm boss, so you can bolt just about whatever you want on there.

An engineering project like this does not come cheap: it'll be 450 CAD // 365 USD to get behind these bars, however a nice carbon bar plus a nice stem is also not too far off this price tag. With that, you get a 2-year warranty...and you can tell people RSL stands for Ride Secret Loamers.

Get it at Trek Bikes.