While some pros still ride with aluminum cockpits (mostly to stay within UCI weight limits), I’m quite fond of carbon wherever you can get it. Not only does the Bontrager Race XXX Lite stem tip the scales at a scant 120g (as tested), but it does so much more than just reduce weight.
Bontrager Race XXX Lite 31.8 Features:
- Bontrager’s lightest, stiffest stem thanks to OCLV carbon construction
- 180 degree faceplate design distributes clamping forces evenly over a larger area
- Unique integrated bolt thread design is lighter and stronger than traditional designs
- Carbon-friendly steerer clamp helps spread out clamping load on lightweight steerers
- 4-bolt handlebar clamp holds bar securely and evenly distributes forces over a wider area
- OCLV carbon construction absorbs road vibration and provides an ultra-efficient interface
- When installed on a carbon steerer, this stem requires at least 5mm of spacers above and below the steerer tube clamp area
- MSRP: $229
Stiff and light stem
Weight is king when it comes to aftermarket road bike components. While you can discuss this feature and that feature, the least common denominator is always how much it weighs. But, that race to the bottom need not overlook the other characteristics. In this case, the Bontrager Race XXX Lite carbon stem is svelte, but it also improves ride performance and handling.
With all their benefits, carbon stems are still not as common as their aluminum counterparts. Stems bear a significant amount of load, so I’m guessing that there aren’t as many companies who can make a stiff and responsive carbon stem that undercuts their aluminum counterparts on weight. At 120 grams, the Race XXX Lite is as light as some of the lightest stems on the market, but that’s not the whole story. The characteristics of the OCLV carbon is such that it’s not only light, but it remains lively.
I backed my way into the Race XXX Lite in that I first tried the Bontrager Race X Lite IsoZone carbon bars with my standard Scott-branded aluminum stem. Going this route enabled me to get used to the bars first, then isolate the stem separately. While the Race X Lite bars offered outstanding performance with an aluminum stem, once mated to the Race XXX Lite stem, the entire package was glorious.
I was concerned that the 7-degree rise on the Race XXX would make the bike feel too racy. My previous stem was also 110mm, but was a more modest 5-degree rise. The subject of negative or positive rise will be left for another day as purists loathe positive-rise stem installation. That being said, I ran the XXX exclusively in negative rise (or standard) mode. The extra 2 degrees dropped my riding position slightly and actually improved overall performance without putting too much stress on my body. I actually preferred the new position.
My first ride on the Race XXX was an eye-opener. I’m a huge fan of carbon bars and have ridden many different varieties. What became immediately evident was just how important the stem is. Most of the time I think of it as the necessary hunk of aluminum that connects my bars to the steerer, but now I understand just how vital it is in the whole system.
The Race XXX dramatically improved the responsiveness and overall performance of my Scott Foil. Topping off the Foil with the Bontrager double-whammy has taken the handling and ride comfort to an entirely new level.
Standing climbs and sprints were lag-free in all regards as the cockpit responded to every ounce of rider input. That instant responsiveness is really what gives this stem such high marks. The subtle improvements in vibration reduction are swallowed up in the quick and agile handling it affords.
On top of the excellent handling, the stem really holds both carbon steerers and carbon bars like a champ. Just a little carbon grease, proper tension and I have been good-to-go with creak-free performance since day one.
The Good:
- Out-of-the-park responsiveness
- Adds subtle dampening to improve the ride
- OCLV carbon is a work-of-art
- Clamps like a champion on carbon steerers and bars
The Bad:
- 5-degree rise would have been nice
- Requires 5mm spacer on top for carbon steerers
The Bottom Line: Bontrager Race XXX Lite Stem
If carbon stems represent the last frontier, I’m hanging out here with my chaps and trusty horse. Without question, the Race XXX Lite stem is well worth the investment. Its responsive handling and light weight makes this stem a worthwhile discussion for riders looking for an extra edge in performance.
Buy Now: Visit Bontrager.com or your local Trek dealer
