Factor O2 VAM Disc review

Lean, mean and incredibly nimble, the Factor O2 VAM Disc takes feather-weight road bike performance to a whole new level - it's practically faultless

Factor O2 VAM Disc
(Image: © Aaron Borrill)

Cyclingnews Verdict

An out-the-box hill climb weapon


  • +

    Exquisite aesthetics

  • +

    Stiff and light chassis

  • +

    Super-fast and reactive on the climbs

  • +

    Predictable handling

  • +

    Superb value for money at this spec-level


  • -

    Ride quality can be quite hard at times

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Pandering to the needs of both the traditionalist and the new world order of disc-brake actuation, the Factor O2 VAM represents the British firm's most athletic road bike to date. Designed to excel in the high mountains where steep, unrelenting inclines are the order of the day, it's not surprising that the raw, unpainted carbon frame has been plastered with the VAM moniker. After all, these three letters are synonymous the world over with climbing mastery.

Having recently returned to the upper echelons of the sport, supplying bikes to WorldTour outfit Israel Start-Up Nation, Factor is looking to re-establish itself as a serious contender in the highly competitive performance road bike space with the O2 VAM.

But just how good is it? A 600km road test through the challenging topography of the Surrey Hills would prove the ideal stress test to answer that question.

Factor O2 VAM Disc road bike

The no-frills, high-performance Factor O2 VAM Disc (Image credit: Aaron Borrill)

Mark of the best

Underscored by an oversized downtube and bottom bracket area, slimline seat stays and tapered fork legs the Factor O2 VAM Disc is an intriguing thing to behold, isn't it?

While it adheres to the now-contemporary bicycle design blueprint of dropped seat stays and semi-aero tubing, it was designed with one goal in mind: featherweight performance, as alluded to by the VAM logo. 

But why the VAM reference? Well, VAM is an acronym for velocita ascensionale media, an Italian term used to describe the rate at which a rider can climb (average ascending speed). It's a subliminal and tasteful cue that adds impetus to the bike's lightweight demeanour.

Visually, the frame is naked and sports a raw yet functional aesthetic, and the unidirectional carbon-fibre monocoque provides a stunning contrast to the glut of flashy paint jobs popularising the pro peloton of late. Pictured here in stock guise, the only references of colour are the gloss-painted black Factor word-mark logo, red VAM lettering and stylish swooshes scattered about. Each of which can be tailored to meet your design requirements through Factor's in-house Prisma Studio program. This is the colourway you want, though.

Compared to its predecessor, the cable routing has been tidied up - both internally and around the headset, where an integrated Black Inc bar-stem replete with heat shrink tubing takes care of the wires and hoses. 

Lightweight recipe and geometry

Save for the additional fork size and minor alteration to the trail number, changes over last season's Factor O2 are difficult to spot and represent more a step up in the manufacturing technique and materials used rather than geometry numbers.  

For starters, the carbon-fibre moulding recipe has been updated to help improve stiffness, maximise internal surface smoothness and ensure a better level of carbon compaction through the use of sophisticated internal latex-covered mandrels. The result has culminated in an exceptionally light frame which tips the scales at under 700g. Our fully built test bike weighed in at 6.78kg (56cm).

The VAM utilises three different types of fibres - TeXtreme, pitch fibre and boron fibre - in its construction. TeXtreme is widely known for its decorative weave pattern and while many manufacturers use it purely for its cosmetic properties alone, its 'spread tow' application is better suited for the innermost layers where it has saved weight (around 20 per cent) and improved stiffness.

The most expensive material is the pitch fibre - or high modulus carbon fibre, as it's more commonly referred to in the industry. Its brittle nature (pre-curing) means it's very difficult to work with but its superior strength has seen it used as a reinforcement measure in the chainstays, down tube and top tube.

Boron fibre is another difficult material to manipulate. While it's been applied in and around the seat tube to reduce what Factor calls 'the oil can, buckling effect caused by thin materials', it also offers a notable compliance benefit when it comes to bumpier terrain and lengthier spells in the saddle.

The sum of its parts

As with every model in the Factor portfolio, the O2 VAM Disc can be purchased as a frameset or full build (it's also available in rim-brake guise). Our test bike arrived as a full build and came tricked out with a Shimano Dura-Ace Di2 R9170 hydraulic groupset as its centrepiece. Comprising a 52/36T chainring combo and 11-30T cassette, this particular drivetrain is geared more towards overcoming gravity than straight-line shunt but can still adequately operate at high speeds, albeit at a slightly higher cadence.

Factor has become synonymous with its in-house skunkworks component division, Black Inc, and naturally appoints its bikes with as much of these parts as possible. In this instance, the VAM makes do with a Black Inc-branded seat post, one-piece bar-stem, out-front computer mount and Black Inc 30 lightweight wheels. The balance of the build is garnished with CeramicSpeed bearings in the headset and PF30 bottom bracket, Factor-branded bar tape, carbon cages, bolts, rubber grommets and thru-axles, and a Fizik Arione R1 carbon saddle.

Factor O2 VAM Disc road bike

Vittoria's Corsa TLR 28C tyres provided a good trade-off between straight-line and cornering speed (Image credit: Aaron Borrill)

 Ride, handling, performance 

The O2 VAM is one of only a handful of bikes that I've managed to gel with almost immediately. The aggressive geometry matched to its lean construction means it's ready to attack the horizon line from the first pedal stroke. It's super responsive, not only to pedal inputs but sudden directional changes too, owing to the ultra-stiff bottom bracket area and taught chassis. Despite it lacking the outright straight-line speed of the Cannondale SuperSix EVO, it's no slouch and can work up a decent head of steam with little fuss. 

Of course, you can always unlock extra top-end by swapping out the stock Black Inc 30 wheels for deeper Black Inc 60 rolling stock but this changes the VAM's distinctive character and will only really work if your regular training routes feature predominantly flat roads. If, however, the topography is lumpy and rolling the Black Inc 30s are more than up for the task and provide a communicative platform from which to steer - allowing you to confidently lean into its huge reserves of grip to fully maximise cornering speed. It's all very intuitive.

The Black inc 30 wheels are also fairly immune to cross-winds/sudden gusts and track predictably but you'll need to fiddle a bit with tyre pressure to eke out a balance between pliancy and performance. My psi ratio of 45 front/55 rear using the Vittoria Corsa TLR 28C tyres seemed to provide a good trade-off between straight-line and cornering speed. The rigid and appreciably stiff platform of the O2 VAM has a propensity to err somewhat on the harsh side of the ride quality spectrum which is fine on smoother sections of asphalt but rougher, more abrasive surfaces can get uncomfortable. 

Yes, you could trade up some parts if it's a more cosseting ride that you're after but, as I've already stated, this will only take away from the O2 VAM's communicative character and sully the overall racy feel. The only recommendation would be to dabble with tyre choice and pressure - the O2 VAM can accommodate rubber sizes of up 30mm.

Factor O2 VAM Disc

The Factor O2 VAM is a master of situations where the road angle tilts upwards and gravity comes into the equation (Image credit: Aaron Borrill)


The Factor O2 VAM Disc can easily hold its own against the segment's best road bikes. It's unquestionably light, superbly efficient on the flats and descends with predictability, sure-footedness and poise. Sure, there are faster bikes out there but unless you're riding at the highest level of the sport or testing it back-to-back against its rivals in a controlled environment those nuances are imperceptible to us mere mortals. 

The O2 VAM doesn't profess to be a jack of all trades. It's a master of situations where the road angle tilts upwards and gravity comes into the equation. This is a place where it's at its happiest.

As far as lightweight climbing bikes go, the Factor O2 VAM represents the zenith of the genre and doesn't pretend to be anything other than what it says on the tin. If it's pliancy and outright speed you're after then you're in the wrong place - go find an aero road bike instead.

Log book

  • Temperature: 9-24 degrees
  • Weather: Sunny, mild
  • Road surface: Dry, mixed surfaces
  • Route:  Tarmac, B roads, rolling hills
  • Mileage: 644km

Tech spec: Factor O2 VAM Disc Dura-Ace Di2

  • Price: £8,999
  • Frame: TeXtreme, Toray, Nippon Graphite Pitch-based fibre
  • Size: 56cm, large
  • Weight: 6.78kg (actual, large)
  • Groupset: Shimano Dura-Ace Di2 R9170 hydraulic
  • Crankset: Shimano Dura-Ace 52/36T, 11-30T cassette
  • Pedals: Favero Assioma DUO
  • Wheels: Black Inc 30
  • Tyres: Vittoria Corsa TLR 28C Graphene 2.0 tyres
  • Brakes: Shimano Dura-Ace hydraulic
  • Rotors: Shimano Dura-Ace SM-RT900 160mm front/rear
  • Bar/stem: Black Inc integrated
  • Bottle cages: Black Inc carbon
  • Bearings: CeramicSpeed bottom bracket and headset 
  • Seatpost: Black Inc VAM
  • Saddle: Fizik Arione R1 carbon

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