Frameset
Frame
Toray®, Nippon Graphite® Pan-Based Fiber
Fork
Factor O2 VAM Svelte / Svelte Disc
Weight
885g
O2 Shimano Ultegra
The current generation of the Factor O2 VAM is a dedicated lightweight racing platform that introduces a distinct aerodynamic focus to the brand's climbing category. Launched in mid-2023, the frame is defined by its ultra-slim, UCI-limit tube shapes, most notably a top tube that tapers to roughly 10mm at the seat cluster. Factor also moved to an integrated seatmast paired with an external sliding seatpost, eliminating the traditional seatpost clamp to save weight and manage deflection. The resulting chassis is reported to weigh around 730 grams painted in a size 54.
This bike is built strictly for competitive climbers and aggressive riders who prioritize absolute weight savings and uphill efficiency over compliance or casual cruising. While it adopts modern practicalities like a T47A threaded bottom bracket and clearance for 32mm tires, its core identity remains tied to steep gradients and high-intensity efforts.
$8,199
Image pending
Build
Size
Inventory
| Stack | 542mm |
| Reach | 384mm |
| Standover height | 772mm |
| Seat tube length | 503mm |
Fit and geometry
Factor revised the O2 VAM’s geometry for this generation by raising the stack height by 10mm across the size range, while keeping the reach measurements unchanged from the previous iteration. This subtle shift allows riders to achieve a powerful climbing posture without requiring an excessive number of headset spacers, though the overall fit remains decidedly race-oriented.
The handling geometry leans heavily into agility. With trail figures hovering between 58mm and 60mm across most sizes, the steering is exceptionally quick. This low trail number explains the highly reactive front end noted by reviewers, prioritizing rapid line changes and low-speed maneuverability on steep climbs over passive, high-speed stability.
The frame features short 406mm chainstays on sizes 49 through 56, keeping the wheelbase tight and the rear wheel tucked closely under the rider for immediate acceleration. The size 58 extends the chainstays slightly to 410mm to maintain balanced weight distribution for taller cyclists. Across all builds, the bike is equipped with a Black Inc integrated barstem featuring a compact 80mm reach and 120mm drop, encouraging a tucked, aggressive position when descending or pushing the pace on flat terrain.
Full specs
Groupset
Shift levers
Shimano Ultegra Di2 R8100
Front derailleur
Shimano Ultegra Di2 R8100
Rear derailleur
Shimano Ultegra Di2 R8100, 12-speed
Cassette
Shimano Ultegra 12-speed, 11-34T
Chain
Shimano Ultegra 12-speed
Crankset
Shimano Ultegra Di2 R8100, 52/36T
Bottom bracket
T47A
Front brake
Shimano Ultegra hydraulic disc
Rear brake
Shimano Ultegra hydraulic disc
Front rotor
160mm
Rear rotor
140mm
Wheelset
Front wheel
Black Inc 28|33 wheelset (700c)
Rear wheel
Black Inc 28|33 wheelset (700c)
Cockpit
Stem
Black Inc Integrated Barstem (integrated stem/handlebar)
Handlebars
Black Inc Integrated Barstem (reach 80mm, drop 120mm)
Saddle
Not specified
Seatpost
27.2mm round (not included)
Builds
The O2 VAM build ladder is strictly premium, offering four complete electronic groupset options: Shimano Ultegra, Shimano Dura-Ace, SRAM Force, and SRAM Red. Both SRAM builds explicitly include integrated power meters, while the Shimano builds do not list them as standard equipment.
Beyond the drivetrain, the component package is identical across the entire range. Every build utilizes the same Toray and Nippon Graphite carbon frame and Svelte fork, paired with a T47A threaded bottom bracket. Factor also equips every model with the Black Inc 28|33 carbon wheelset, a lightweight, shallow-profile hoop designed specifically to complement the frame's climbing focus. The cockpit is uniformly handled by the Black Inc integrated carbon barstem.
Because the frame, wheels, and cockpit remain constant, the price and weight differences between models are dictated entirely by the groupset. The Ultegra and Force builds offer the core performance of the chassis at a slightly more accessible tier, though they remain high-end investments. The Dura-Ace and Red builds represent the absolute ceiling of the platform, utilizing flagship components to push the complete bike weight as close to the UCI minimum as possible.
Shimano Ultegra
$8,199
Selected
SRAM Force w/ Power Meter
$8,399
Shimano Dura-Ace
$9,999
SRAM Red w/ Power Meter
$10,299
Reviews
Reviewers characterize the Factor O2 VAM as an uncompromising climbing specialist that demands a skilled, attentive rider. On steep gradients, the bike excels. Testers note that uphill, it is "one of the absolute best bikes one can have" (Cyclonline), praising its immediate power transfer and exceptionally low weight. The chassis is highly responsive under acceleration, making it eager to surge forward out of the saddle.
However, this sharp reactivity requires active management on descents and rough pavement. The steering is described as "sensitive to every solicitation" (Cyclonline), meaning the bike responds instantly to rider input but can feel nervous if not handled with a firm grip. At high speeds, testers warn that the bike "must be driven with a certain determination, otherwise it is not very precise and unstable" (Cyclonline).
Ride quality is similarly focused on pure performance rather than endurance compliance. The stiff frame and integrated seatmast transmit significant road feedback, resulting in a ride that "concedes little or nothing to ride comfort" (Cyclonline). While it accommodates wider tires that can help mute some chatter, the underlying architecture is firm. It is a machine built for experienced racers willing to trade plushness and straight-line stability for absolute climbing speed and agility.
