Despite its status as a relative newcomer to the industry, Factor Bikes is already known primarily for its willingness to depart from traditional frame limitations in pursuit of on-road benefits. The O2 Road Frameset represents a different kind of departure for the British brand, eschewing much of the aerodynamic wizardry that defines Factor's flagship models with a more classic design and some always-appropriate weight loss. Given the fact that so many of the pros at One Pro Cycling are choosing the O2 for all-purpose race applications ranging from the fast courses of Britain and Korea to Utah's grueling mountains, we believe the results speak for themselves.
The O2 doesn't have the OTIS head tube/fork construction or Twin Vane down tube of Factor's flagship model, but it does feature the same uncompromising carbon lay-up and an angel-of-the-mountains-worthy 740g of claimed frameset weight. The low weight and deceptively responsive drive spine seem mutually exclusive, but Factor manages to bridge the divide while maintaining an admirable amount of long-mile comfort. It's not as smooth as an endurance-minded steel frame, but the O2 doesn't have the ass-on-asphalt punish factor so common in the sub-800g, high-mod category.
The O2's characteristics are the product of a collaboration between some big names in the cycling industry and a big name in automotive aerodynamics. The project was started by bf1systems, a motorsport firm that dabbled in cycling with the revolutionary (and non-race-legal) Factor 001 and Vis Vires framesets. A group of two-wheeled visionaries recognized the potential of bf1systems' designs, snapped the Factor name and technology up, and have since translated it into race-legal framesets with the ultimate aim of sponsoring a World Tour team.
Though not as pronounced as the One and One-S models, the O2's aerodynamic benefits are still readily apparent to the naked eye. The vertically oriented tubes' bullet-nose face and truncated tailing edge will be no surprise to anyone staying abreast of industry advances because the shape babysits airflow from the point the frame encounters it till long after it's detached and dissipated into wake. The abbreviated rear face is especially important for two reasons. First, it reduces the negative vacuum of trailing drag that traditional NACA tube shapes produce. Second, it doesn't turn into a destabilizing parachute when crosswinds and road conditions shift the yaw angle outside of a NACA profile's near-zero comfort zone.
The frame's aerodynamic features extend to such subtleties as a hidden seatpost clamp, tucked-away seatstays, internal cable routing, a Di2 junction box, and the inclusion of an integrated stem/bar unit designed to work as part of a drag-reduction system with frame and rider. Frankly, we expect this roster of wind-cheating features from high-end aerodynamic road frames; given Factor's penchant for going above and beyond what's expected, it's no surprise that they're all represented here.
The fact that the aerodynamics don't come at the cost of comfort is a surprise, though. We've got to stress again that the O2 isn't as buttery smooth as a classic, lugged steel frame or a heavy, carbon cobbles machine, but it does transmit a lot less harshness than the non-traditional tube shapes and seatpost would suggest. Maybe this is because of the low chainstay juncture and shape, or maybe it has something to do with the EM2 RGicarbon lay-up. Given one that one of Factor's co-owners has a 15+ year pedigree producing carbon frames for an impressive list of boutique brands, we suspect the latter might play a significant role. The O2's EM2 RGicarbon construction involves three different carbon moduli that balance the vibration damping and durable compliance of lower and middle moduli with the unyielding stiffness of Pitch Fibre, a material that is as unabashedly stiff and light as its name is unabashedly British.
Since it's the star material in EM2 RGicarbon, we'll linger a bit on Pitch Fibre. Factor isn't shy about claiming that Pitch Fibre is the lightest, stiffest material that can be shaped into a bike frame, so you might assume three things here: 1) Pitch Fibre is extremely difficult to work with, 2) it's very expensive, and 3) Factor jealously guards the exact details of its lay-up schedule. You'd be correct on all fronts. The one insight Factor gives into its process is the use of a program called Fibersim, which Factor uses to "ensure that we put the waste into the garbage can and not into the frame." Fiberism helps keep material to a minimum, resulting in fabric cuts and construction as discerningly meticulous as the wardrobe of brand-ambassador and sartorially gifted cyclist David Millar.
The frame is also accessorized like a bespoke tailored suit. In addition to the fork and seatpost, Factor packages the O2 with a Ceramic Speed (yep, ceramic) bottom bracket, a Cane Creek 40 headset, a compression plug, steering tube spacers, a spare derailleur hanger, bar tape, and a few other unlooked for but indispensable items. Though the tires aren't included, the O2 enjoys generous clearance, allowing 28mm tires and opening up terrain possibilities that were previously unimaginable for a race bike like this.
- An all-new racing frameset that's already proven at the pro level
- Carbon lay-up targets weight loss and wattage firepower
- Aerodynamic design with European motorsport pedigree
- One-piece carbon bar and stem keep the cockpit aerodynamic
- Black Inc. carbon seatpost and integrated clamp mechanism
- Ceramic Speed bottom bracket included
- Internal, sheathed routing makes for easy cable install
- Generous tire clearance accommodates up to 28mm donuts
- Not compatible with mechanical groupsets