Open MIN.D. 2020

With a design that is focused away from the race crowd, Open's MIN.D frameset is an excellent option for general riding. Balancing low weight with loads of stiffness at the front end and bottom bracket along with a compliant rear end, the frame is perfect for cruising broken roads in comfort and then smacking it up some climbs.

The ride

Everything that I want in a road bike when I'm not racing is provided by the MIN.D. My riding tends to consist of heading into the Mendip hills with their steep, tough climbs and riding out to the coast at Weston. The roads are broken, so comfort is key, but the steep climbs mean that I need a stiff and lightweight bike. I also want sharp handling to keep things interesting.

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The MIN.D won't ever compete on the flats with today's race bikes with their aero tube shapes, but in all other regards I have found Open's first road bike to be worthy of the 'superbike' moniker. If you're not bothered by the current trend for front-end integration and aero then this is a fabulous option.

My first ride on the MIN.D went straight into the hills, and the combination of stiffness and low weight (Open claims 870g for a medium frame, 335g for the fork) was instantly noticeable. The bike climbs beautifully, rewarding out-of-the-saddle efforts with instant surges in pace.

With the rather low rear end created by the sloping top tube, it can look, at first glance, like a rather upright bike. But the 135mm head tube on this size small keeps things racy should you want to slam the stem like I did. That isn't to say that this is a long and low racer. A 71-degree head tube angle means that the 535mm stack and 361mm reach create a riding position that suits the general purposes of the bike.

While measurements up top create a comfortable riding position, drop down the bike and you'll find a setup that is anything but slack. The rear centre of 405mm and front centre 578mm (measurements from hub centres to BB) with a BB drop of 73mm create a tight wheelbase of 971mm. This is what I think really makes the MIN.D fun to ride, allowing you to flick the bike around both when climbing and through tight corners.

I have had an absolute blast letting the brakes off and flying down the tight, narrow lanes where the road surface, gravel and patches of grass growing though the tarmac often combine to give you only one possible line, with a mid-corner bunnyhop needed to make it through. Having a bike that feels so chuckable and responsive while still being unfazed by bumps results in a lot of fun.

When I wasn't pushing the limits of grip, the MIN.D is a comfortable place to be, cruising along the flats with a very smooth ride quality. Open has incorporated three design features that really help here. First, the continuous seat tube that extends right from the bottom bracket, running for the majority of its length at 25mm where a bike with a 27.2mm seatpost would use a 30mm external seat tube. This is really thin and is one of the advantages to a continuous seat tube as it allows for extra flex just where it is needed.

Joining that seat tube are two incredibly thin seatstays. Again, these add flex to the frame where it is needed, but the main factor affecting comfort is the space for massive road tyres. Open says that you can fit up to 32mm tyres in the MIN.D and the 32mm Schwalbe tyres fitted to this test bike certainly provide plenty of comfort if you want it. Strictly speaking, when mounted on a rim with a 21mm internal width, those Schwalbes actually sat at just under 34mm.

Playing with the tyre pressure is really important with so much volume. For relaxed spins around the lanes I let the tyres down quite a bit, to around 50psi. This gave a feeling of floating over all those harsh road surfaces but it did feel like the tyres were dragging a little when climbing, so I went up towards 65psi when heading into the hills.

Frame and fork

Open's designer, Gerard Vroomen, has called this first road frameset the MIN.D for a very specific reason. It stands for minimal design, and while that might make you think that this is a basic disc-brake road bike, there's quite a bit going on when you take a closer look.

First, the basics. The full carbon frame (no, Open doesn't specify what grade of carbon) centres around a BB386 bottom bracket.

The rear end has 142x12mm spacing and the fork uses a 100x12mm spacing.

Seat tube

Vroomen opted for a continuous seat tube, removing the need for a seatpost and clamp. One of the main reasons, beyond the clean aesthetic, is that the tube can be made very thin, sitting at just 25mm in diameter. This, Open says, adds comfort, and I have to say that this is one of the more comfortable road frames that I've ridden.

The seat tube is topped by the minimalist cap that secures the saddle in place. While you need to be really careful measuring your saddle height before cutting it down, you do have a bit of wiggle room with the top cap offering up to 15mm of added height. If you get things really wrong then Open's Measure Once Cut Twice top cap adds 15-35mm of height. (Open has a video to explain it.)

Securing the top cap in place is a small compression system secured by two tiny grub screws. I have to say that I had my concerns about these and still have some reservations about the system. My first worry was that a compression system this small wouldn't hold the top cap and, therefore, the saddle in place. Thankfully, it hasn't budged at all.

> How to set your saddle height right

My second concern was that on our test bike, the heads of the grub screws are tiny and the metal feels very soft. Open says that the production models use a far harder metal for the screws, but I'd still be careful and as always, use a torque wrench when tightening.

Smartmount 160

Sorry to those of you who are fans of 140mm disc brake rotors – and I'd count myself in that crowd – but the MIN.D frame and fork are both set up to take 160mm rotors without needing adaptors.

Vroomen says that you gain braking power and extra modulation for just a slight weight penalty, and while I can't say that I've ever had an issue with power from a 140mm rotor, I will concede that I'm on the lighter end of the scale and your more average human will see the benefits of the larger rotor. Not needing ugly mounts is certainly far sleeker.

Thruthreaded dropouts

Open uses the derailleur hanger threads to secure the thru-axle too. It is apparently lighter, and there's not much more to say than that. It secured the wheel as you'd expect.

Internal routing: electronic and 1X mechanical

The frame is set up to accept all electronic shifting systems as well as 1X mechanical groupsets and 2X Shimano R8000 and R9100 groupsets – not 2X SRAM mechanical because it doesn't have the frame stop for the front gear cable, Shimano's is built into the groupset. It's all accessed via a single port on the non-drive side of the down tube, with the SRAM Red eTap AXS build that I have here looking very smart.

Aesthetics

Talking of looks, I really like the general aesthetic of this bike: the double triangle design without dropped seatstays and a great rainbow colour fade inside the chainstays.

Build options

The MIN.D is only available as a frameset but you can have one built up if you buy from an Open dealer. The world is your oyster, as long as you want an electronic or 1X mechanical groupset, and disc brakes. Seeing as you're spending £3,240 on the frameset, I doubt that's going to present too much of an issue.

Value

And that leads us nicely on to value. At this price we're into the truly high-end part of the frameset market and the competition is tough, but the MIN.D does come in just a little cheaper than another non-aero carbon frameset, Colnago's C60, which is £3,499.95.

> Buyer’s Guide: 25 of the best production frames  you can build into your dream bike

The MIN.D isn't marketed as a race bike, but it does compare well with the likes of the Trek Emonda SLR at £3,500 and Specialized Tarmac SL7 at £3,750, although Giant's TCR is far cheaper at £2,349 and boasts an integrated seatpost. All three of these rivals also come with aero claims.

Conclusion

Overall, the Open MIN.D is absolutely fantastic. It balances stiffness with comfort that can really be felt on rough roads. The handling is razor sharp, making this a fun bike to ride both uphill and back down.

Verdict

Brilliant frameset for fast climbing, and it's comfortable too