Road & Gravel Bikes

Factor simplifies its sizing by using a consistent, race-proven geometry across its entire range of high-performance road and gravel bikes. This unified approach means that whether you are looking for the aerodynamic advantage of the OSTRO VAM, the climbing prowess of the O2 VAM, or the all-terrain speed of the OSTRO Gravel, your recommended size will be the same. This chart is your primary reference for all Factor drop-bar bikes.

Time Trial & Triathlon Bikes

Factor's time trial and triathlon bikes are engineered for one thing: pure speed against the clock. The SLiCK and HANZŌ models feature highly aggressive, aerodynamic geometries where achieving the perfect fit is paramount for both power and endurance. A professional bike fit is strongly recommended for this category.

Track Bikes

The HANZŌ Track is a specialist machine built for the unique demands of velodrome racing. Its geometry is extremely aggressive for explosive sprints and precise handling on the banking.

Mountain Bikes

Factor brings its engineering expertise to the dirt with the Lando cross-country mountain bike platform. Available in both full-suspension and hardtail versions, these bikes are designed for modern XC racing with progressive geometry for confident descending and efficient climbing.

A Deep Dive into Factor's Race-First Geometry

Factor's approach to bicycle design is born from the worlds of Formula 1 and aerospace engineering. This heritage is evident in their no-compromise, performance-first geometry. Unlike brands that offer a wide range of "endurance" or "relaxed" fit options, Factor focuses on a race-oriented geometry across their lineup. This philosophy is built on the principle that a bike should be an extension of the rider, providing immediate response, predictable handling at speed, and a platform for maximum power transfer. To choose the right Factor is to embrace this philosophy.

The Unified Geometry Philosophy: A Key Factor Advantage

One of the most significant and unique aspects of Factor's sizing is their unified geometry across the road and gravel range. This means the core fit coordinates (stack and reach) for a size 54 OSTRO VAM are identical to a size 54 OSTRO Gravel. This is a deliberate engineering choice with several key benefits:

• Consistent Feel: For professional riders and dedicated amateurs who own multiple Factor bikes, this ensures a seamless transition between their road race bike and their gravel bike. The body position remains the same, eliminating the need for adaptation and allowing for consistent performance across disciplines.
• Predictable Sizing: It simplifies the buying process. Once you know your size in one Factor drop-bar model, you know your size in all of them. This removes the guesswork often involved when a brand has vastly different geometries for their aero, climbing, and gravel platforms.
• Performance-Driven Design: Rather than detuning their gravel geometry for comfort, Factor maintains its race-proven fit and adapts the bike for off-road use through other means, such as increased tyre clearance and specific carbon layups. They bring the speed of the road to the demands of gravel.

Deconstructing the Geometry Chart: More Than Just Size

For a precise fit, it's essential to look beyond the height recommendations and understand the numbers on the geometry chart. For Factor bikes, these figures define their character:

• Stack and Reach: Factor bikes generally have a lower stack and a longer reach compared to endurance-focused bikes from other brands. This creates a more aggressive, aerodynamic riding position. A size 56 Factor, for instance, will feel longer and lower than a 56cm endurance model from a competitor, demanding more flexibility from the rider but rewarding them with aerodynamic gains.
• The Role of Integrated Components: Most Factor bikes come equipped with a one-piece Black Inc bar/stem. This component is integral to the bike's performance and aesthetics, but it also has major fit implications. The bar width and stem length are fixed. Therefore, a pre-purchase bike fit is crucial not only to determine your frame size but also to select the correct bar/stem dimensions, as changing it is a more involved and expensive process than with a traditional setup.
• Trail and Handling: Factor's engineers meticulously tune the head tube angle and fork offset to achieve a specific "trail" figure. This number dictates the bike's handling characteristics. Across their road and gravel range, they aim for a balance that provides high-speed stability and confidence without sacrificing the sharp, intuitive cornering that racers demand.

The Non-Negotiable Step: A Professional Bike Fit

Given the investment and the uncompromised performance focus of a Factor bike, a professional bike fit should be considered a mandatory part of the purchasing process. The height-based charts in this guide are an excellent and accurate starting point, but they cannot account for individual variations in limb length, torso length, and flexibility.

A professional fitter will:

1. Confirm Your Frame Size: They will use your measurements to verify that the recommended size is indeed the best option for you.
2. Determine Your Component Sizes: Crucially, they will determine the exact Black Inc bar/stem dimensions (e.g., 110mm stem length, 420mm bar width) you need.
3. Optimize Your Position: They will fine-tune your saddle height, setback, and cleat position to ensure maximum power, comfort, and injury prevention.

Booking a fit before you place your order is the single best way to guarantee that your new Factor will fit you perfectly from the very first ride.

Sizing FAQ & Advice

Why is a Professional Bike Fit Essential for a Factor Bike?

Factor bikes are high-performance machines engineered to the tightest tolerances. While these charts provide an accurate starting point based on your height, a professional bike fit is the crucial final step. A fitter will analyze your specific body proportions, flexibility, and riding goals to fine-tune your position. This ensures you can comfortably and efficiently extract the maximum performance that a Factor bike is designed to deliver, especially given the limited adjustability of the integrated Black Inc cockpit systems. A fit session will determine the exact component sizes you need to order with your frame.

I'm Between Two Sizes. Which Should I Choose?

If your height falls on the cusp of two sizes, the best choice often depends on your riding style and body proportions. If you have a longer torso and arms, or prefer a more stable, stretched-out feel, sizing up is often a good choice. If you have a shorter torso, prefer a more nimble and responsive handling feel, or want to achieve a lower, more aggressive "pro" riding position, sizing down is typically recommended. It is generally easier to make a smaller frame fit larger (with a longer stem or more seatpost) than the reverse. Consulting with a bike fitter is the best way to resolve this dilemma.

How does the OSTRO VAM fit compare to the O2 VAM?

Because of Factor's unified geometry philosophy, the fit is identical. A rider who is a size 54 on an OSTRO VAM will also be a size 54 on an O2 VAM, and their position on the bike will be the same. The choice between them is not about fit, but about performance priorities. The OSTRO VAM is an all-around aero bike, optimised for aerodynamic efficiency across all conditions. The O2 VAM is a specialist climbing bike, prioritising absolute low weight and a reactive feel on the steepest gradients. Your size remains constant; your choice depends on your terrain.

How does Factor's sizing compare to other high-end brands like Cervélo or Specialized?

Factor's geometry is squarely in the "race fit" category. Compared to a Specialized Tarmac or Cervélo R5, a Factor frame of the same nominal size will have a very similar stack and reach, offering an aggressive, performance-oriented position. However, it will feel significantly longer and lower than an endurance bike like a Specialized Roubaix or Cervélo Caledonia. The key is to ignore the size number (e.g., "56") and compare the raw stack and reach data between the bikes you are considering.

Is a Factor bike a good choice for a beginner or a rider focused on comfort?

Factor bikes are designed for experienced, performance-focused cyclists. The aggressive geometry, particularly the low stack height, requires a good degree of flexibility and core strength to maintain comfortably. A beginner or a rider whose primary goal is a relaxed, upright, comfortable position would likely be better served by an endurance-focused brand. A Factor is a tool for speed, and its fit reflects that singular purpose.