Open Cycle was founded by Gerrard Vroomen of Cervelo and Andy Kesslar of BMC. They launched the lightest production mountain bike frame at the Sea Otter Classic in 2012. The Open O-1.0 was born, and I was fortunate to own, ride and race the best 29er hard tail.
9.5
Coming off the heels of the 2011 Leadville Trail 100 I was already contemplating my return trip to test my will at the infamous one day race. What could I do differently to best my already solid time? I had the best training possible and felt relatively great on race day. My nutrition was dialed, too, but I couldn't help but wonder what a super light bike between my legs would do. Could a lightweight hard tail or fully rigid bike give me an edge? There's only one way to find out, and that's to build one.
Design
A lot of great design great thinking when into this bike. Aesthetically I was drawn to the minimally branded, flat black and subtle graphics, but beneath the surface is engineering that translates into a really light and responsive ride. From the BBright bottom bracket, beautiful internal and adaptable cable routing, S3 front derailleur mount, wire stays and thoughtful geometry, the collection of technology make for one unique and sexy bike. While expensive, setting you back a cool $2,900 for the frames (which includes the super stiff Rotor 3D+ crankset), this bike oozes pure XC racing.
At a glance, the atypical steep head tube angle of 72º seems odd, making for a seemingly twitchy front end, but somehow it feels great and just right for being a 29er. It always felt precise and responsive. The flattened out seat and semi-flex chain stays soften the ride without sacrificing power transfer. The squarish/oval shaping of the down tube also contribute to the snappy handling.
The lightest production hard tail 29er on the market is also the sexiest.
Parts
I went all out with my Open build, ENVE components for the wheels and cockpit, a RockShox SID World Cup fork up front and a SRAM X.0 Trail 2x10, featuring Grip Shift and their quad-piston brakes. To round out the package I rode a fi’zi:k Antares Tundra saddle, Look S-Track pedals, Schwalbe Racing Ralph EVO tires and Arundel carbon cages. All put together it tipped the scales at 19 pounds on the nose.
I worked with the awesome folks at Pro Bike Supply who helped me order the Open O-1.0, spec the parts for compatibility and partially build the bike before shipping it out to me directly. They were super helpful and quick to put everything together. Kudos to them for making a complete virtual bike purchase experience so great.
I really put the Open through its paces, having raced an 8-hour event, Leadville, a gravel grinder and a full season of XC racing in Northern California. The bike really shined at the start of every race where I was able to accelerate quickly with power and ease. The obvious advantage came through when the trail got steep. I was able to float up the hills with a bit more ease, granted a lot weight savings came in the form of static versus rotational weight. Still, this thing is a rocket uphill.
Race It
For long endurance races like the Boggs 8-Hour or the Leadville Trail 100 the Open O-1.0 felt very comfortable with 8 plus hours in the saddle. The only problem I experienced was in the fi’zi:k Antares Tundra saddle and not the bike. The fi’zi:k is light and fairly comfortable within an hour or two of riding, but because of the flat shape there was too much pressure on my junk to endure for long periods of racing. I prefer the feel and ergonomics of Specialized Body Geometry saddles where pressure is placed squarely on your sit bones.
I raced a lot of XC events in 2013, including the Sea Otter Classic, the Tamarancho Dirt Classic and the Lemurian Shasta Classic among the highlights. I found the Open to be very trail capable. The flattened out wire stays took the edge out of most trail chatter. The only major issue came from the Rotor chain rings later in the season. I kept experiencing mis-shifts and dropped chains. Now I consider myself a seasoned bike mechanic and know everything was correctly tuned, but the design of the rings just didn't cut it.
9.5
The Open O-1.0 is an XC racer's dream, but all the engineering feats come with a rather steep price. Otherwise a 10, regarding its design and performance, the costly nature of the frame, non-traditional BBright convention and ok long-term chain ring performance bump it down a tiny notch.
I owned the Open O-1.0 for a year before finding a new owner. I sold it because I started racing for a Specialized sponsored grass-roots elite team and couldn't afford to have another gorgeous bike collect dust at home.