A Flat Circle: Our OneUp Alloy Handlebar Review Got Pretty Deep


A Flat Circle: Our OneUp Alloy Handlebar Review Got Pretty Deep

It’s not every day that an aluminum tube inspires heavy philosophical questions about the bike industry. But that’s exactly what the new OneUp alloy bar did for Travis Engel. It’s a lower-priced alternative to the brand’s unique, innovative carbon bar, and after just a month, Travis is questioning a few long-held beliefs. We think he should relax. It’s only an aluminum tube.

I’m just old enough to have known a world before Nintendo. My earliest video game memories were of an Atari 2600. The graphics were ugly and the joystick moved like frozen toffee. But in 1987, my parents brought home the 8-bit Nintendo Entertainment System, with its brighter colors and refined controls. Then, five years later, our 16-bit Sega Genesis leapfrogged the Nintendo in every way, including its shiny black plastic skin. That console would eventually get plugged into a glitzy Sega CD … which kinda sucked. Many of its high-profile titles were essentially grainy cutscenes separated by button prompts. But it took me a while to admit that to myself. At the same time that congress was roasting Sega CD’s notoriously clunky Night Trap for its misogynistic violence, I was on my third playthrough trying to get the best ending. I didn’t know any better. Video games had never let me down before, so I just couldn’t believe a step backwards was even possible. I eventually came to my senses, and when I needed cash for my first mountain bike, I sold my Sega CD.

To be clear, the goal of Night Trap was to trigger traps that would capture these black-suited villains. But the fact remains, it was a terrible game.

I think back to that experience a lot these days. The bike industry is known to take the occasional step backwards. Sometimes it’s obvious. Like (you guessed it) thru-headset cable routing. But other times it’s not so simple. Sometimes, a trend will emerge with so much promise that we get swept up in the hype, and it takes a while for us to see it clearly. One trend that’s only recently come into full focus is the 35mm handlebar clamp diameter. The idea makes sense. Big diameters have paid big dividends for axles, steerer tubes and crank spindles. And handlebars have gotten a lot wider, so why shouldn’t the clamp diameter get thicker? But quiet dissent surrounding 35mm’s harsher ride quality has started to surface. Long before I’d heard any of that, I made the leap to a 35mm Race Face bar. It was lighter than its smaller-diameter equivalent, and claimed to be stronger. I had no complaints, but it wasn’t until I went back to a 31.8 bar that I realized its subtle flex added comfort without any noticeable impact on steering response. I also realized that, although I’d broken three handlebars back in the 25.4 era and bent as many BMX bars, I have never broken a 31.8mm bar … knock on wood.

My old 35mm Atlas bar. Can’t bring myself to get rid of it.

Despite all this, the 35mm clamp diameter has continued to grow in popularity, especially on new-bike OEM spec. I’ve been told by some bike and handlebar manufacturers that the reasons are mostly cosmetic. Frame tubes, fork stanchions, even stems have gotten thicker. 35mm bars just look better on today’s bikes. There are still plenty of 31.8mm bars available aftermarket, but it’s become uncommon to see them on new high-end builds. And I doubt that this pendulum is going to swing back any time soon. It’s just not a big enough deal to most people. So, instead of fighting it, some handlebar manufacturers are working with it. You’re hearing the word “compliance” a lot more, especially on carbon bars where manufacturers can fine tune at a material level. But I think the best solution so far has come from OneUp.

Using a flat-oval cross-section at the bend, OneUp’s bar actually improves on the flex of most 31.8 bars. It’s noticeably more comfortable, but still offers the strength, weight, style, and lateral-stiffness benefits of 35. Many drop bars have taken a similar wing-shaped approach for years, so it’s likely to catch on in the flat-bar space. In fact, the house-brand Santa Cruz bars on the 5010 I just tested have almost the same shape. But these are not cheap. The carbon OneUP bars are $159.50. And the Santa Cruz bars are $170. So now, four paragraphs in, I’ll finally get to the goddamn point.

OneUp also makes a stem. It does a great job at holding the bars. But it also has the clever feature of 5mm steerer-tube clamp bolts, so you can use the same tool to adjust your headset preload as straighten your bars.

OneUp just launched an aluminum bar with the same flat-oval concept. It is also not cheap, at $89.50. But flagship alloy 35mm bars from Chromag, Deity, and RaceFace are all the same or more. And listen, I didn’t drag you through an overly wordy intro just to get stuck in a cost/benefit analysis of every handlebar on the market. The reason I think the OneUp alloy bar deserves this much attention isn’t that it’ll save you $60. It’s that it is a simple way to right one of the industry’s wrongs. You don’t have to swap both bar and stem to go to 31.8. And you don’t have to spend even more to go to carbon. And you don’t have to spoil what I must admit is a better-looking cockpit. OneUp has offered a plug-and-play way to get a better ride experience. And maybe now, five paragraphs in, I should actually talk about that experience.

You can see the wide profile from the top…

… and the thin profile from the front.

During testing, I just happened to be going back and forth between a traditional 35mm bar, 31.8mm bar, and these OneUp bars. All were alloy, 800mm wide, and bolted to 140mm forks with 29-inch wheels. The immediate difference in feel between the OneUp bars and the traditional 35mm bars was subtle most of the time, but not subtle when impacts reached enough intensity to spark that initial flex. There wasn’t a magical floating feeling like I’ve felt on outliers like the linkage-driven Fasst Flex bars or the 22.2mm titanium bars from BTCHN’. But there was a notable lack of “spikes” on fast rocky descents, when I would lean in, elbows out.

I tested the 35mm rise bar, but OneUP also makes a 20mm option.

Does what it says on the tin.

I can’t say I felt much noticeable relief from the dreaded arm-pump, even compared to a traditional 31.8mm bar. Maybe that’s a symptom of my nagging tendency to death-grip when I don’t need to. Also, I had no less soreness during long climbs or traverses. When I was just cruising along, the suspension fork felt like it was offering all the float I needed. But suspension can only do so much. There are rods and pistons and bushings and o-rings. The very tips of high-frequency impacts always seem to pierce through that mousetrap. It’s why RockShox introduced their low-tech “Buttercups,” which are essentially tiny bumpers between the fork lowers and the fancy innards to take the edge off. That’s exactly what the OneUp handlebars do. Mainly, I just had less discomfort and less distraction in the moments when it was most important to avoid both.

Comparing the 35mm OneUp to a traditional 31.8mm bar, I couldn’t sense a benefit to either with regards to brute-force front-wheel control. But I don’t doubt that a more assertive rider could. And that dynamic gets to the heart of why OneUp’s approach is such a breath of fresh air. Often, the “evolution” of mountain bike tech favors those on the shreddier end of the spectrum. Slacker head angles, longer wheelbases, generally heavier bikes might leave some riders feeling forgotten in the industry’s quest for gnar. But the OneUp alloy bar is kinda for everyone. It’s for people who want the added comfort, but it’s also for people who are charging hard and need all the responsiveness they can get. And now that I know there’s a reasonably priced bar that can do both, I’m ok that it’s also for people who just like the way it looks. Actually, it’s kinda growing on me. I guess even I can be a sucker for cool-looking gear sometimes. It’s why I’ve got a Playstation 5.


  • Price: $89.50
  • Rise: 35mm, 20mm
  • Clamp Diameter: 35mm
  • Width: 800mm
  • Upsweep: 5°
  • Backsweep: 8°
  • Weight: 337g (35mm), 318g (20mm)
  • Material: 7050 – T76 Aluminum
  • Finish: Fine shot peen, black anodize, glossy logos compatible with OneUp handlebar decal kits
  • Decal Kit Colours: Red, Green, Blue, Orange, Purple, Silver, Gold, Turquoise, Matte Bronze, Oil Slick and White

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