How to get a good bikefit

29 Nov 2023 / 10 Dec 2024

Even if you’re sure that your chosen bikefitter knows what she’s doing, the result may disappoint if you don’t.

drawing demonstrating horizontal chain stay length measurement

Often, I hear that people don’t want to spend money and time on bikefit arguing that two different fitters produce different results — so what’s the point than.

I’m a proponent of a professional fit: I was surprised to learn a couple of things about how my body interacts with the bike at my first session, even though I had cycled for over 20 years by then.

A human body have bigger tolerances than bike components, but the significant differences in bikefit numbers may happen because one doesn’t communicate with the fitter to explain what they want/need — if they even understand that themselves in the first place.

It’s like coming to a doctor or a lawyer. They can only help you if you properly describe the problem and are involved in the process.

drawing demonstrating auxiliary chain stay length measurement

1. Understand your goal

I’d say that there are three popular goals:
• improve performance, in general or for a particular event/discipline,
• get rid of a certain pain/fatigue point or deal with an injury,
• make sure the fit is correct and won’t create problems in the future.

Listen, even “I want to look cooler on my bike” is a valid goal — just don’t forget to actually tell it to the bikefitter. Be honest with her and yourself, that’ll help a lot.

track bicycle with short chain stays and split seat tube

2. Decide how far you’re ready to go

There are two main scenarios in bikefitting: either to fit a bike to the person, or get a bike to the person.

In first case, you’ll come to the fitter with your own bike and you’ll try to adjust it to achieve the best result possible considering the limitations of your bike’s geometry and components. Compromises may have to be made, but if your bike is a given, it’s hard to go around that.

In second instance, you’ll be put on a “mule” — an apparatus that allows infinite and unrestricted adjustments. After finding the best body position in space, you’d then need to find a bike allowing to recreate it, with the fitter’s assistance.

This approach is only comfortable if the fitter actually has the mule — which costs a pretty penny. Hence, the higher price of such bikefits.

road bicycle with short chain stays and split seat tube

As an alternative, there may be a quality cycling trainer (smart bike — which also allows to change position in a wide range, even though not as quickly & conveniently as with the mule), or a set of various bicycles, from which it would be possible to find one most close to the optimal position and then keep adjusting it until the best position is achieved.

All that said, I’d say you shouldn’t pay too much attention to the bikefitter’s equipment.

There’re “commercial” bikefitters at bike shops with a full set of expensive stuff that — combined with their one-month express course in bikefitting — would not allow to solve non-obvious issues with the fit. And then there’re experienced and knowledgeable specialists — who, even without all the lasers, goniometers, motion capture and pressure mapping devices, can properly fit onto a bike even a circus bear.

2.1. Additional costs

Keep in mind that some components could be changed — that would usually be: saddle/seatpost, stem/bars, shoes/pedals/cranks. Oftentimes, the bikefitter will have some stock of her favourite parts (and we’ll assume that’s for their properties and not for her good markup on a low cost of supply).

You should decide for yourself how much you’re ready to spend to achieve an optimal result. If you don’t want to buy components from the bikefitter, you’ll need to get them elsewhere and get back to her, which may result in an increase in the cost of the service — depending on the particular person, I guess.

close-up of road bicycle with short chain stays and split seat tube

Also, there is an approach where before buying a new bike, you come to a “sizing” session where the fitter evaluates you approximately and advises on which bike in what size to purchase, after which you come to the full fitting session.

In my experience, that doesn’t always work well.

If I was buying a $$$$ bike and not sure the size/fit, I’d rather spend a couple of hundreds for a full bikefit beforehand rather than get a wrong size and regret it.

Let alone that swapping components to get a good fit after the quick-and-dirty sizing may happen to be more costly than to come to an additional session with the bike (which would usually be heavily discounted anyway).

2.2. Extra effort

Your body changes with time and training. Again, there are two approaches: let’s name them the “realistic fit” and “theoretical or physio-based”.

In the latter the fitter tries to apply her knowledge of physiotherapy to understand what you theoretically could achieve with your position on the bike.

If you happen to deal with this kind of educated fitter, decide if you want to do non-cycling exercise such as yoga or weightlifting to improve your flexibility and/or strength.

If you’re not ready for that, tell her. Otherwise, you may get a fit suitable to your better, but not actual, self.

bicycle with thin seat tube and integrated seat post

The realistic fitting approach is not to try and change the cyclist, but to merely fit the bike to their body as it is. This doesn’t cancel the fact that the body will change (hopefully, to the better :)

3. Be open to a relationship

Whichever approach, a good fitter will have a vision of how your bikefit could develop with time.

If you’re rather new to the sport, you’ll likely not only get stronger on pedals (with less pressure on the saddle), but also stretch out farther and lower — meaning the handlebar and saddle will have to be adjusted accordingly.

If you are a mature and seasoned cyclist, it may be that your power and flexibility will, vice versa, somewhat decrease with age.

Thus, if only to to fit for your future self, the position will have to be readjusted in a while, according to the physical changes in your body.

So, a decent bikefitter will provide you with a sheet describing the result of the fit in words and numbers. Those could be handy, whether you keep working with her, or try another fitter for your next session for a second opinion.

Or, learn how to adjust the bike to your changing situation yourself — remember that bikefitting is not a one-time endeavor, but a continuous process.

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