Modern Track Bike Fit: Why Your Track Frame Should Be Bigger Than Your Road Frame

Over four years ago, we published a blog answering the age old question - what size track bike do I need?

Unfortunately, it’s not a simple answer. With so many unique frame geometries and methods for measuring, it can be complicated to know exactly which way to go. We also appreciate that it can be daunting to spend thousands of dollars on a frame without knowing its exact fit. This blog looks to guide you in the right direction by outlining which measurements to look out for, as well as the thinking behind it.

As with any blog, this is a discussion piece - so if there’s anything you don’t agree with, or feel needs more attention, please feel free to comment with your thoughts below. We are not bike fitters, nor do we have a background in biomechanics. These are our thoughts and experiences towards current track cycling bike fits and the thinking behind them.

Since our last blog post, new bike fitting trends have been established, and new purpose built frame-sets have been released, that respond to new trends and aim to optimise to the latest UCI rules. 

The Problem 

The part where most people trip up, is that sizing differs drastically from brand to brand and cycling discipline to discipline. That is to say that not all road and track bike sizes are created equally. Traditionally, road bike frame sizing has been based off of the top tube length. A 54cm top tube is traditionally a  medium, 56cm is a large, and 58cm an extra large. However, Article 1.3.016 within the UCI rules puts weight on the front-centre measurement - which directly relates to where you’re able to position your handlebars (up to 100mm in front of the axle) This has led to a change in frame sizing in relation to the height of an athlete.

Article 1.3.016 of the UCI technical regulations (the UCI ruling) stipulates that the front-centre (measurement taken from centre of BB to centre of front axle) can have a maximum measurement of 650mm. 

For track bikes, the best way to represent the frame's true size is by the front centre measurement (I will explain in detail below). This means that now some frames are being measured in a not so traditional top tube length style.

Why the front centre?

I suppose for reference, Article 1.3.022 of the UCI ruling states that “In no case shall the front of the handlebars exceed the vertical plane passing at horizontal distance of 100 mm from the the axis of the front wheel spindle”. Noting this ruling helps to understand my points below on why the UCI takes the frame measurements from the front centre, rather than the top tube length.

1. It accounts for head tube angle and fork offset

Two frames can have the same top tube length, but different head tube angles. A slacker head tube (The smaller the angle , the slacker it is) pushes the front axle further forward, simultaneously changing how the bike handles. More importantly, front-centre captures this relationship, while the top tube alone doesn’t.

2. It ties directly to handlebar position limits

Article 1.3.022 in the UCI ruling (and practical bike handling) keeps the bars from extending further than 100mm ahead of the front axle. 

This restriction, as well as the front-centre limit isn’t about rider comfort but more so about consistency. By fixing the bars relative to the front axle, the UCI can ensure that no matter the head tube angle or fork offset, frames can’t be stretched to create effectively longer front ends. Front-centre becomes the true reference point, because it captures those geometry variables and keeps effective frame sizing comparable across all manufacturers, sizes and steering geometry.

Our UCI reach gauge allows for easy measuring when it comes to checking whether your setup fits within this 100mm ruling. 

3. More reliable measurement point

To accurately compare the length of different track bike framesets, the front-centre measurement is more reliable than the top tube. The primary challenge with top tube measurements stems from aero-shaped seatposts and non-traditional steerer tube systems. Due to the difficulty in determining the true midpoint of these areas, some brands measure from the front, while others measure from the center. This inconsistency can lead to a misleading discrepancy of 2-3cm, misrepresenting the frame's actual length. However, the centre of the bottom-bracket and front axle spindle is easily identifiable.

Stack height, not head tube length

Akin to the top tube, the head tube doesn’t tell the full story either. This ties directly into the top tube vs. front-centre debate. When the head tube gets taller, the effective top tube becomes shorter due to the backward angle of the head tube. From this, the value of stack height becomes apparent.

Stack height is the vertical distance from the centre of the bottom-bracket to the top of the head tube. You can have a very small head tube, but the overall stack height could be much taller relatively. This deception stems from the varying angles of seat tubes and head tubes found on different frames and sizes. Just like front-centre, stack height is a much more comparable and reliable measurement pointSo just as front-centre better represents reach and handling, stack height more accurately represents the front-end height.

How should you size your track bike?

With a solid grasp of track frame sizing, we'll now explore the connection between your road and track frame dimensions in the subsequent section of this blog. First off, many of the casual track cyclists you see at your local velodrome may very well be  on bikes too small for them. Up until about 2018, track cyclists would typically ride the same size bike as they would on the road to replicate the bike fit for both disciplines. Back in the day of steel frames track bikes, some riders would even size down to reduce how much the frame would flex. For the majority of athletes (aside from elite level athletes), we don't need to worry too much about frame stiffness optimisation due to composite technology and its superior stiffness to weight characteristics.

The frameset is at the core of all the geometric requirements for an optimum aero and bio-mechanical fit. Yes, you can swap out stems and bars to get a longer reach, but without a large enough frameset you will forever be chasing your tail with compromises to riding performance and handling. These limitations come from how short the front-centre is as outlined above.You may have noticed it's fairly difficult to get a hold of a XL track bike in the second hand market. This is because they are in hot demand with riders sizing up and adopting the long and low aero bike fit trend. XL-sized track bikes are a rare find on the second-hand market. This scarcity is a result of fewer taller riders purchasing XL bikes in the past, as they tended to size their track bikes similarly to their road bikes, before the current trend of longer frames became established. Younger and shorter athletes, such as juniors and many females are in luck, as there are plenty of medium and large frame options out there for you to choose from. These sized frames for those athletes are more than adequate to optimise a more aero track bike fit. At an Olympic level however, even riders at 160cm are riding these larger frame-sets!

For a quick comparison guide, here is a quick spreadsheet of some Olympic medal winning riders from around the world and what size frame they were using for the Paris 2024 Olympics. It's important to note that these riders have been meticulously set up on these bikes. Just because you may be a similar height to one of these riders, it may not mean that the size bike they rode will also be suitable for you. 

Different Requirements

The requirements of your road and track bike can be very different. Track races span across distances from as little as 200 metres, up to 50km. Compared to elite road athletes who could be racing and training more than 200km on the road at a time.

Over the recent years we have seen an increased focus on the interaction between rider and bike. This development has seen an overall increase in track frame sizing. 

The purpose of this next section is not to tell you what size frame you should get, but more so highlighting the purpose of sizing up your track bike when relating it to the two distinct disciplines of track cycling.

Sprinters

Track Frame

If you look at all of the world class sprinters, they all generally have a long position with their bars at a height where they can comfortably deliver their power whilst having their forearms close to parallel to the ground.

A long front end with high bars has been a desirable setup over the last couple of Olympic cycles. The extra length means that the rider can launch themselves further forward during standing starts, getting over the bars a little bit more and extending the period that the rider can put power through the pedals over the deadspot zone in the crank revolution.

As of 2025 the trend is currently shifting again in favour of going back to lower cockpits but this time in pursuit of achieving lower total system height as we see drops in relative saddle height too. When coupled with shorter cranks that open up the hip angle, the athlete can fold themselves deeper to achieve a lower position for a reduced frontal area. 

Road Frame

Typically speaking, the majority of a sprinter's work is done on their track bike and road bikes are more so used as a form of recovery in between efforts and sessions alike. For this reason, you may want to consider a shorter, and more upright position on your road bike. 

Consequently, a sprinter's road bike is typically sized more "traditionally," likely appearing smaller than their track bike when aligning with current trends in track frame sizing. It might seem counter-intuitive, when aiming for a more “relaxed” position, to consider a smaller frame than your track bike. Most road frames from the same brand will feature a taller stack height and a shorter top tube when compared to their track frame equivalents of the same size.

Another simple, yet important feature to consider is the brake levers. On a road bike, a comfortable and easy ability to change gear and reach the brakes is essential. If you have ever tried riding another bike which is 2-3 sizes too big, you will notice that it is much more difficult to reach the brakes when in such a long and stretched out position.

So, when looking at the table above, it is important to note that the 160cm athlete would ride a road bike with a front-centre of 625mm (Or XL in traditional sizing) due to reasons stated above.

Endurance

Track Frame

Just like sprinters, endurance athletes are moving towards more “aero-minded” positions with the emergence of different styles of mass start handlebars. Athletes look to rest on their hoods with their forearms parallel to the ground for longer and longer periods of time.

Although this may be more aero, it can be unsustainable - especially as we see longer fits where you’d be putting more weight through your arms than through the saddle. However, just like the sprinters, the endurance athletes of the 2024 Paris Olympics also had longer positions (when comparing to the positions of the 2021 Tokyo Olympics) with their bars at a height where they can comfortably deliver their power whilst having their forearms parallel to the ground in the “hoods” position. 

We believe this mostly comes down to the change in UCI ruling which occurred between Olympic cycles. Reiterating Article 1.3.022 of the UCI ruling mentioned above which states that “In no case shall the front of the handlebars exceed the vertical plane passing at horizontal distance of 100 mm from the the axis of the front wheel spindle.” However, between the Tokyo and Paris Olympics, athletes competing in bunch events were subject to ruling stipulating that this distance could only be 50mm from the axis of the front wheel spindle. 

Endurance athletes have recently opted for larger track bike frames due to this rule change. This has seen them achieve a bunch position closely resembling that found on their pursuit bikes with their forearms parallel to the ground and relatively flat backs.

Road Frame

Endurance track athletes will typically do the majority of their training on the road. This means that they must have a road frame which allows for the relative comfort and sustainability required to ride the hours they must in training.

That being said, most endurance track athletes will also race on the road and a much more “aero-minded” position will be adopted on their road bike too. However, similarly to sprinters it is unlikely that an endurance athlete will be able to size their road bike as aggressively as their track bikes.

As I mentioned above, road frame sizing has stayed relatively “traditional”. As an example, if we look at our new Altias Fusion frameset you will notice that our size “small” has a top tube length of 576mm, “medium” with a measurement of 601mm and so forth. Based on “traditional” sizing our small would be considered at least a large. However, as explained above, the new track frames focus on going longer and lower when compared to road frames which for the equivalent size and brand will typically have a much taller stack height. 

This reinforces why it’s important, when choosing a new frame, to consider the actual measurements on the geometry chart rather than relying on size labels like S, M, or L.

Conclusion

Thanks to a focus on aero-testing and validation we have seen drastic developments in track bike fitting from the more “traditional” set ups. Regardless of whether you're a sprinter or an endurance athlete, we believe you should consider choosing a track frame that is larger than your road bike frame. What size ultimately comes down to the frames geometry, event, components, and purpose of your track or road bike. The ideal front-centre length for your track bike is primarily determined by your height, although it's important to remember this is a general guideline. As discussed, frame stack height and your unique physical proportions will also influence the most suitable frame size.