Review: BMB Reverse Raise Stem - The Stem That Wants to Change Mountain Biking

Both of these options brought up points and concepts that very much go against the grain of how conventional frame and stem design works. What Mondraker took away in stem length they could be said to have added to the top tube, and Rulezman suggests something similar, only they say to consider sizing a frame up.

Of course, to say that either of these brands just made a stubby stem and called it a day would be wholly unfair - and they both have a whole slew of other refinements across the bike. Rulezman's reasoning again suggests longer rear-centers. This is something I'm a big fan of, and where I consider a possible new avenue of design springing up. They also suggest that the 10-20mm stems brought forward by Mondraker all those years ago were somewhat limited by other geometry dimensions not compensating for the inherent rearward weight bias that will come when you move to a stem that is both shorter and higher.

Both of these ideas are genuinely interesting, and I particularly enjoyed Seb Stotts's article above regarding Rulezman's offering. However, today the stem in question is from the American brand Be More Bikes, and we're focussing on their unique take on stem design, as well as questioning whether looks can be deceiving and it's not that different after all.


Bold Looks, Yet Even Bolder Claims

The bicycle industry is full of passionate people, and Bronson Moore is one of those people. His stem isn't something he's thrown together in CAD, ordered a thousand units of and then happily moved on and forgotten about. Speaking to him at Sea Otter earlier this year it's clear he lives and breathes this weird and wonderful creation, and I have so much respect for people like him.

The stem looks wild, and its claims are similarly grandiose. BMB's copy breaks down the stem's features into two key areas - the raised height and the reversed offset. Let's start with the former.

In no particular order, some of the claimed benefits are that the stem puts a rider's arms at a better angle to the bars for descending with confidence, and encourages a bend at the elbow and more room to maneuver before your joints reach their maximum extension. The increased distance between arms and feet is said to grant more leverage over the bike, help you ride with more weight through your feet and less with your hands, and let you have a calmer and more comfortable attack position, similar to what you would have on a dirt bike.

In terms of the reversed offset, the copy states it can calm the floppy feeling of slacker bikes, give better control to let you load side knobs more effectively, and enable the rider to make tighter turns; the position is supposed to stop the front wheel from tucking in extreme steering angles and give you a greater feel for the front tire's contact patch, meaning you can carve the rear with more confidence.

These claims could prove to be game-changing. Unlike the other novel ideas challenging "stem convention," this stem doesn't claim to be part of a greater geometry concept. They state specifically that you don't need to upsize your bike.

So far, so radical.


Can This Position Be Achieved With Conventional Components?

During testing, I became curious about how this actually compared to typical parts that we had in our Squamish HQ. I've ridden with high-rise bars before, and like so many of us I'm familiar with the limitations, as well as the gains. Sometimes, with an extremely tall front end going between the edges of the tire feels like crossing no man's land. There is balance, but transitions between turns feels somewhat vague, and the front can lack grip and small deflections can start to be a real cause of instability, especially if there isn't enough weight on the front wheel to keep it balanced and tracking straight and true. Being on the Y-axis isn't so bad, nor is being lent, but for me, the transition through the vertical plane can feel unsettled.

I fitted the rather imposing A76 bars from Answer which, it may surprise you, feature 76mm of rise. The bars put my hands at a very similar height to the BMB stem, if only 80mm further forward. To explore this further, I rotated the 40mm stem 180 degrees and refitted the bars. I went for a ride around the car park and two things were confirmed to me - I didn't particularly like it, and yet it felt oddly familiar.


Climbing Impressions

Riding the stem puts you in a very unorthodox position, which is kind of the point. Immediately I thought of people I've met over the years who have back issues, and how this would be a great option to try. I also thought of people wishing to learn how to bunny hop and, again, I thought this would be a great teaching aid. I then went onto the trails and the endless possibilities of what this stem could do began to dry up.

How a bike fits is very subjective, and I'm not going to bore you by telling you that how a bike fits my body should be the single most concerning thing that you should happen across on Pinkbike today. However, I found that when riding along the flat and climbing this stem put me in a tiring position that I would find hard to hold over long days on the bike. Normally, I like to have a degree of support from my bones, joints and skeleton, and I don't believe we want our core to be engaged for great chunks of time. I like my elbows to be just back from locked, with my arms supporting my upper body even on bikes where the front is low.

The RR stem had me feeling more like I was in something similar to a plank position on gradual climbs, and a town-bike when things got steeper. I'm happy to admit I'm not a gym fiend, but I would say that I never normally struggle in terms of upper-body bike fitness. However, my triceps felt like they were constantly preloaded as they tried to keep the front weighted. When it got steeper or more technical, I felt like I had to practically put my chest on the stem. On the right climb, this stem not only lacks grip on the front, making you see-saw front and back as you search for traction, but is also downright exhausting.

Front-wheel lifts are a breeze, mind you, and if you're somebody that snagged their front on roots or square edges then this stem will help that.


Descending Impressions

To ride this stem on a regular bike, in this instance a size large Transition Spire, felt completely out of sorts. I don't wish to be the bearer of bad news, but I don't think you can make such a massive change to how the rider's mass weights a bike and not treat it as a wholesale change.

Front grip was lacking, and searching for it could result in lunges and pushes. There was a balance to be found when leaning, but the window was small and ineffectual. More often what happened was you would find a lean angle that you could begin to trust, only for the front to begin to wash and the large spread between contact patch and hand would come around and punish you, and you could feel like your hands would lose a lot of height. This wasn't so much the sensation of handlebar flop, where you feel like you fall into the inside in some ways because the tire is gripping, but rather an enhanced and exaggerated version of the wheel washing, a bit like hitting a wet root while dragging your front brake.


Preloading the front while braking was also a real challenge when grip was at a premium, as was that feeling of falling onto rails as you enter a turn, weighting the outside foot and modulating the grip with your inside hand.

On flat-out, straighter sections, it could feel okay - but only in the way a high-rise bar would, and it offers benefits with not only the trade-off you're familiar with, but a near turbocharged version of them because of the reverse stem. I'm a big believer in heavy-feet-light-hands but this takes the theory beyond an extreme that I am comfortable with.

I spoke with Bronson, and he seems accepting that this stem won't be for everyone and that it will suit certain frames, positions, and techniques more than others. He even explained that he wants to use this stem as a stepping stone to a more holistic concept, which sounds like a great idea to me. A balance between two points is the result of both placement and consideration, and I'm curious to see the frames that he eventually makes to account for the super high front of his stems. He's also working on a second version with slightly less height to hopefully fit a greater range of riders on a wider variance of frames.

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Pinkbike's Take

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