There’s a great deal to be said for versatility, especially in the hyper-specialized (no pun intended) world of premium road cycling. Aero-this. Climbing-that. Cobbled-there. It’s the world of bikes-turned-racecars, so it’s incomparably refreshing when something like the Open UP comes rolling around, lightly promising to be all things to almost all people. Gravel roads? Sure. Singletrack? With the right wheels. Road riding? We can do that. Criterium? Reaching, but maybe. With the ability to run both 700c standard road wheels and 27.5 mountain bike hoops, the UP presents a quandary of confusion for us, the “right tool for the right job” obsessed, an obsession that leads to owning ten vastly similar – but different – bicycles. We asked ourselves the question: Can we turn that mentality completely on its head? Can the UP, with one set of wheels, conquer almost everything from tame singletrack to centuries with a modicum of adequacy?
To find out, we slapped our house 27.5″ MTB hoops on one of our demo UPs. Some WTB rims we had kicking around, a pair of DT Swiss 240 hubs. Nothing crazy, but a well-mannered setup for well-mannered riders, supplanting the Zipp 30 Course road setup that had been happily residing on the bike. For tires, we selected the exact same capable rubber that was mounted to the Zipps, but in 27.5″ trim, the slick Maxxis Refuse in a whopping two-inch width. Supposedly the arrangement would give the bike roughly the same overall wheel/tire diameter, thus maintaining frame geometry/handling characteristics, but proffering additional pneumatic suspension and increased grip. Admittedly the bike had been quite capable with the 700x40mm setup previously mounted, only getting over its head on high-speed, loose-over-hard descents and highly technical singletrack.
First things first: The weight. The 27.5 Maxxis rubbers out-hefted the 700c version by a fair margin, but our house-built hoops were a bit lighter than the Zipp setup, and it translated into barely a 70g weight gain between the two setups, with the 27.5 variant clocking in at 17.52lbs overall. That said, any weight that was added went directly to the very edge of the rotating mass of the bike at the wheels, a potential detriment to how easy the bike is to accelerate and change direction with.
As the UP is something of an “all-road” beast, we started out with pavement. With tires aired to a cushy 35psi (lest you judge, give this piece
by our friends at Bicycle Quarterly a quick glance when it comes to low pressures), we set out. Compared to the 700c variant, the 27.5 Refuse felt…well, it felt slow. While the Refuse in 700×40 was no spring pavement chicken compared to the Vittoria Corsa tubulars we’re well-acquainted with, they roll acceptably quickly, and with enough effort get up to speed. Well enough, in fact, that they can pass as true road rubbers in a pinch. The 27.5 version? Honestly, they felt like mountain bike tires. Slick they may be, but rolling resistance was unacceptably high. The bike was difficult to push on the pavement, and once it was, it was hard to keep momentum. It was a similar feeling to riding a fatbike on the MTB side of things, after spending decades on narrower tires. The chubby Maxxis needed constant input to keep cruising. Of course, none of this was that
shocking – the Refuse in 27.5 trim is roughly three times
the weight of a typical 700c road racing tire, and its 60tpi tubeless-ready casing, while utterly bombproof off-road, offers a less-than-supple ride on tarmac. We trudged on, towards dirt ahead, with higher hopes than before.
Off-road, we were secretly hoping the huge tires would cause the bike to come alive, a drop-bar singletrack slayer of epic proportions, with the smaller wheel size supplying nimbleness we hadn’t felt with the big 700c hoops. Alas, it wasn’t to be. The bike instead felt weighted down and sluggish, squishing instead of popping, lumbering instead of limbering. But, that same feeling gave the Open oodles of grip on the dirt, a planted, confident feeling as it ripped downhill with its massive tire contact patch. It went from the “oh-shit-this-could-go-pear-shaped-quickly” feeling of speed on dusty descents to the smooth tracking of a Mercedes S-Klasse ripping the Autobahn at 200km/h. Just as well, we hoped the 27.5 slick tires would lend themselves to that same motorcycle-like limitless grip feeling we’d gotten from the 700c variant on pavement. Again, our hopes were dashed – the tires were simply too big to really lean over into their sweet spot, instead feeling awkward and ungainly on tight tarmac twisties. The Open’s notoriously sharp geometry was effectively dulled by all the heavy, dense rubber, and we found ourselves wanting, always feeling like we’d chosen the wrong tool for the job at hand.
Does this mean the 27.5″ wheel is one to be tossed by the wayside when it comes to the Open UP? Of course not. Equipped with two sets – one 700c, one 27.5, the opportunities for niching present themselves nicely. A slicker, 30-40mm tire on the 700c set for “all-road” adventures (we’ve recently started supplying the UP with Compass’ svelte 35mm and 44mm slick tubeless tires in that regard), and a true MTB knobby on the 27.5″ wheels could be the real jack-of-all-trades arrangement. With two sets of wheels, the Open becomes a far more versatile weapon than with just one, a bike that can tackle nearly anything laid before it, at least for the cyclist seeking one bike to cover an extremely broad range of rides. At the end of the day, we found ourselves not wishing to pit the two wheel sizes against each other, as is normal human nature, but instead allow them to compliment each other in one stable…which is likely the way it should be.