Just in: Ultimate USE clamps 35mm Vyce stem onto Boom carbon MTB bar

The lightweight, British-made loop Ultimate Vyce stem has been around since 2016, but now U.S.E. has dialed their wedge clamper up to 35mm with greater strength & stiffness for aggressive trail riding. The move to the larger diameter mount also brings a new Boom Carbon riser bar, promising more control without the harshness found in most 35mm trail bars. Light, stiff & not harsh sounds like a good combo, so we are going to pop it on a trail bike and see how it rides…

U.S.E. Ultimate Vyce 35 mountain bike stem

This new version of USE’s Vyce mountain bike stem, scales up the simple loop design to work with modern 35mm bars which are becoming more common, especially on trail to enduro bikes. While most of those type bikes include large, chunky & heavy stock alloy stems, the Vyce is a simple & light upgrade option.

Machined entirely in the workshop of U.S.E. at the foot of the South Downs in southern England, the Vyce 35 promises all the stiffness you can need in an easy to use setup.

Based on the same dual-wedge design as their original Vyce, the 35mm version scales that wedge up to clamp the larger bars, adding a second stainless steel bolt to clamp it all together.

The way that wedge design works, the two pieces of the larger wedge next to the bar are clamped together with the two opposing bolts. As the two sides (above left) are pulled together, they push the third piece (above right, with pink grease) away, evenly applying force to both the bar and steerer tube, pushing them apart into the loops of the all stem body. (This image above is actually of the 31.8mm version that uses a single pinch bolt.)

The design of the steerer wedge’s bars slotting into the sides of the bar wedges keeps it all rather snuggly together, so all the parts don’t fall out when you remove the stem. The three-piece wedge is still separate from the stem loop, so even though the fit is snug, when you take the stem completely off the bike, you do need to hold the pieces together.

U.S.E. offers the Ultimate Vyce 35 stem in two lengths – 40 & 50mm – with claimed weights of 108g & 118g, respectively. Our 40mm sample stem hit that right on the mark.

The £90 / $123 / 108€ Vyce 35 stem was developed with British 4X champ Scott Beaumont for strength & light weight, and should be stiff enough for any trail riding & enduro racing too. It is CNC machined in-house from heat treated T6 alloy, shot-peened for strength, sent up the road for shiny black anodizing, then comes back in-house for laser etching & packaging.

We’ve bolted ours up to a mid-travel trail bike, and intend to seem how it balances stiffness with a new carbon bar that claims a less harsh ride.

U.S.E. Ultimate Boom Carbon 35 mountain bike riser handlebar

When you make a new 35mm stem, you need a new bar to go with it. I personally haven’t really bought into the 35mm bar+stem combos yet, as I felt like I had enough stiffness with 31.8mm, while almost every 35mm setup I have ridden felt overly stiff or harsh. To be fair, I haven’t spent much time on high-quality 35mm carbon bars. So when U.S.E. promised a more forgiving layup designed to balance control stiffness with vibration damping characteristics, I was open to try something new.

U.S.E. says that they developed a new tapered carbon layup specifically for this new Boom 35 bar to maintain that stiffness that 35mm promises, while eliminating (or isolating) much of the harshness that can plague larger diameter bars.

The £135 / $185 / 162€ Ultimate Boom Carbon 35 mountain bike riser handlebar is 800mm wide, with cut marks to take it down to 740mm. The wide bar is made from matte finish UD carbon, and features 30mm of rise, with 7.5° of backsweep & 5° upsweep. U.S.E. claims an uncut weight of 220g for the Boom 35, but ours weighed just 206g, and will likely drop under 200g once I chop about 4cm off of it to fit through the tightly spaced trees in on our local trails.

The new Ultimate Boom Carbon 35 handlebar gets it name again from Scott “Boom Boom” Beaumont, recent British champ and ex UCI 1st ranked 4X racer. He wanted a light, but stiff bar to match the new Vyce 35 stem, so U.S.E. developed the Boom 35 with their Asian carbon partner – designed in the UK, produced in Asia.

Both the new Vyce 35 stem & Boom 35 bar are available from U.S.E. direct, and though their international dealer network now.

UltimateUSE.com