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What We Ride: Sam’s Open UPPER gravel bike

Sam Challis
23 Mar 2022

Tech ed Sam’s lightweight custom gravel build with Shimano GRX Di2 is fast on-road and off

It’s well documented in the pages of Cyclist magazine and on this website that I’m a fan of the bike brand Open. I enjoyed riding its MIN.D road bike, for similar reasons to why I liked the brand’s original design, the UP: for its pioneering and trend-setting approach to modern gravel bike design.

Cyclist’s former digital editor Peter Stuart gave the lighter successor to the UP, the UPPER, a glowing review back in 2020 and after similarly positive experiences aboard both bikes I decided that I wanted to own one.

In a rare case of a bike journalist putting their money where their mouth is, I bought an UPPER frameset last year.

Barring a switch from post mount brakes to flat mount, the frameset has changed little since Open first released it in 2016. Considering current trends, it may be beginning to show its age slightly with its 700c × 40mm tyre clearance.

That's comparatively small when measured against the most modern gravel bikes, but for someone who doesn’t mind using 650b wheels when I need truly voluminous tyres, a 40mm maximum for 700c isn’t a hindrance.


The UPPER is the same in shape as the UP, but Open says it uses a revised layup schedule and some slightly posher materials to bring the weight down by about 200g or so.

Otherwise, the two framesets share an identical remit: to be a jack-of-all-trades when it comes to drop bar riding.

Open UPPER: Going everywhere fast (because I don’t have time)

The UPPER’s clean lines and simple tube profiles help create light weight and stiffness, while pioneering quirks like its dropped driveside chainstay offer good tyre clearance within the narrow Q-factor afforded by road cranks, while keeping the back end short.

A feature set like that, coupled with a nicely balanced geometry, means the UPPER can switch identities entirely in the time it takes to change the wheelset.

I really like that about the UPPER – it can be a fast road bike with some deep section wheels and 28mm slicks on, rip over light gravel using 37-40mm tyres, or go exploring with some 47mm knobblies and a 650b wheelset.

In fact, that ‘three bikes in one’ rationale was a key factor in the justification of the purchase to my wife, so it's as useful in theory as it is in practice.

Set up in this guise – fast off-road riding – it weighs 7.5kg. That would be pretty impressive for a road bike, but for a gravel bike with the capability the UPPER does, it’s exceptional and I’d say this is evident when out riding.

The bike feels uncommonly lively and often affords a sense of nimbleness off-road that I would liken to riding a race bike on the road.

With a young family I don’t have the opportunity to go off on all-day weekend rides – whether on road or gravel, my outings tend to be limited to 1-2 hours and are about covering ground quickly. The UPPER is ideal in that respect. In short, it’s a blast to ride.

Open Upper: Posh DT Swiss wheels

With the design of the frameset allowing it to be so adaptable, I’ve found the parts that hang off it tend to have more a of marked effect on the bike’s resultant character than if the frameset were more pigeon-holed in its remit.

The best example of this is in the bike’s wheelset and tyres.

In the GRC wheels, DT Swiss was one of the first to consider aerodynamic efficiency in a gravel wheelset.

I explore the ins and out of their design in my review, but ultimately I don’t think they offer much of an aero advantage to riders using realistic tyre sizes going at realistic speeds.

That hasn’t stopped me from growing really fond of the wheels, though. Their 24mm internal rim width supports big tyres at lower pressures nicely, and I think that deep rim, at least in part, helps them feel stiff under acceleration.

What’s more, they have proven themselves to be sturdy and they’re light enough to work superbly on the road with wider hookless-compatible road tyres.

It is rare to find a wheelset that acquits itself so well in several guises. That is what I think makes them excellent and very well suited to the UPPER’s similar levels of adaptability.

I’ve shod the wheels with WTB’s 37mm Riddler tyres. WTB has established itself as the dominant gravel tyre brand and for good reason.

The Riddlers are among the best fast rolling gravel tyres on the market. Their low-profile centre tread doesn’t sap speed on tarmac but still offers grip on easy gravel.

The sidewalls are a little fragile (look closely and you’ll see the tail of a Dynaplug tyre plug in the sidewall of the front tyre) but the Riddler’s suppleness and grip is worth it. In my experience they are easy to install too.

Open UPPER: Shimano GRX Di2 with SRAM-esque customisation

Shimano’s GRX Di2 takes care of the shifting and braking duties. As I mention in my review of the groupset, I think the GRX-specific levers are a triumph in off-road ergonomics that I love using.

I’ve set the groupset up 1× because I’m not especially sensitive to jumps in my cadence and really like 1× gearing as a solution for both gravel and road.

Plus, via the Shimano E-tube app, not having to cater for front shifting means I can set both the upshift and downshift paddles on each lever to perform the same shift function.

It replicates SRAM’s eTap shift logic of using the left lever for easier gears, right for harder ones, and effectively amalgamates the thin, separate shift paddles of Shimano’s levers into one giant paddle. It makes shift control fool-proof even in muddy conditions or over rough ground.

I’ve opted for a 40-tooth chainring and an 11-40 cassette. It’s quite a tight gearing spread but I live in Dorset, where there are innumerable short, sharp hills and even those conditions I’ve never felt the need for anything lower than a 1:1 bottom gear.

My knees may grumble later in life, but for now they seem content to let me grind up the 20% gravel ramps of my home trails without fuss.

Plus, keeping the cassette to 11-40 rather than going to 11-42 means the jumps between gears on the 11-speed cassette are reduced. Although I’m not particularly cadence-sensitive, I’m not going to say smoother gear progression, where possible, isn’t welcome.

Open UPPER: Pro finishing kit

I’ve stuck exclusively with Pro for the UPPER’s finishing kit. Specifically, components from its Discover off-road family.

Pro says its Discover seatpost promises a little extra comfort by way of some flex built into its carbon layup.

While I can’t imagine the effect of its inclusion produces a night-and-day difference over a more conventional post, I reasoned the promise of extra comfort only comes with a 10g weight penalty over Pro’s regular Vibe post, so was probably worth a punt.

It has Dyneema in it too, which Pro says should make it more resistant to impact damage. In my experience, crashing is a case of ‘when’ rather than ‘if’ while gravel riding, so I thought this was a welcome feature.

The Pro saddle on top of it is the off-road version of the brand’s snub-nose Stealth saddle. It’s the same shape, just with a little more padding on the shell.

I’ve found the Stealth to be a great shape for my anatomy, but as the hulls of Pro saddles tend to be very firm, the extra cushioning is welcome. It is an excellent, good value saddle that I would recommend highly.

At the front of the bike, I chose Pro’s Discover Carbon bar. It’s light, stiff and has Dyneema in too for that added promise of toughness, but ostensibly I selected it for its ergonomics.

It matches the Shimano GRX levers perfectly (the bar-to-hood transition is seamless), sports a neat compact bend, and the 20° flare let me go narrower on the tops (for a more aero position position with no trade-off) but still wide in the drops for extra control when required.

I went for the Discover stem purely because it matches the rest of the finishing kit.

It is the right length, it’s not too heavy and all its bolts are conventionally situated. I’m not crazy about the dorky honeycomb decal on the faceplate but the sense of symmetry achieved by speccing matching finishing kit outweighed my ambivalence towards that feature.

Open UPPER: Cherries on top

A couple of extra little details completed the bike for me.

First was a set of Silca Ti cages. While undoubtedly an extravagance, they are light, robust and beautiful. I can’t really explain why, but I like the way they clash with the carbon frameset but pick out the silver of the chain, cassette and rotors.

I should probably mention that they are also excellent at their primary function too. They hold bottles firmly, despite those bottles being easy to remove and replace by hand.

Bar tape wasn’t a particularly fretted-over choice. It had to be black and a little tacky, but otherwise anything would do.

Syncros’ Super Light bar tape was knocking around in my shed, fit the bill and was notably easy to install.

A few Wolf Tooth Precision headset spacers finished the build off. Wolf Tooth makes top-quality aluminium spacers in a range of anodised colours, including a luscious purple. Purple happens to be my favourite colour, so their use adds a personal pop to an otherwise demure build.

Job done.

Sam's Open UPPER spec

  • Frame: Open UPPER (size Large)
  • Fork: Open R-Turn
  • Weight: 7.5kg
  • Groupset: Shimano GRX Di2 (40t, 11-40)
  • Wheels: DT Swiss GRC 1400 Spline 42
  • Tyres: WTB Riddler TCS (37mm)
  • Bars: Pro Discover Carbon (40cm)
  • Stem: Pro Discover (110mm)
  • Seatpost: Pro Discover
  • Saddle: Pro Stealth Off-road
  • Pedals: Shimano XT
  • Accessories: Silca Ti bottle cages, Syncros Super Light bar tape, Wolf Tooth headset spacers

Photos: Lizzie Crabb