As a qualified bike fitter and experienced long-distance cyclist, I can say with authority that one of the most crucial factors in any rider’s cycling experience is the correct bike fit.
When it comes to finding the correct-sized bike for you, it can be challenging. Fitting the bike appropriately is even harder.
There’s so much to consider, such as seat height, reach, crank length, stack, and even handlebar width.
Unfortunately, there’s very little information online to point you in the correct direction when you want to change your fit, and a professional bike fitting is too expensive for many cyclists.
In this article, we will give you all the information you need to give yourself a rough bike fit and how to optimize it, depending on whether you’re looking for comfort, performance, or a combination of the two.
*Note that most of the bike fitting charts in this article are based on road bikes as standard.*
We’ll be covering:
- Road Bike Frame Size Chart
- Bike Seat Height Chart
- Understanding Reach (and “Handlebar Reach”)
- What Stack Height Do I Need? (With Chart)
- What Crank Length Do I Need? (With Chart)
- What Handlebar Width Should I Use? (With Chart)
- Overall Bike Fitting Chart
Let’s dive in!
Not All Bodies (or Bikes) Are The Same
The first thing to understand before grabbing those Allen keys and making bike adjustments is that everyone is different, and so are bikes.
We can give you all the information here to help get a rough fit and make adjustments to optimize that, but there are a lot of variables.
For a perfect fit, we recommend going to see a bike fitter if you can, but we appreciate a lot of people who like to do a fit themselves or don’t want to invest that much money if they don’t cycle a huge amount. So, use these charts as a guide to get you started.
Road Bike Frame Size Chart
Getting the right frame size is essential.
You can make all the other adjustments you like, but if your starting frame size is wrong, you’ll always be playing catch-up with your bike fit, and it’ll never be quite right.
You can use our chart above as a quick reference, check out our frame size video explainer below, or check out our Ultimate Guide to Road Bike Frame Size here to go into real depth on the subject!
Bike Seat Height Chart
Once you’ve got the right frame size, bike seat height is – in my professional opinion – the most important measurement of all.
This chart will give you a rough guide of what saddle height you should have based on the inseam of your leg.
Inseam is measured by standing against a wall with a book at the top in between your legs and measuring to the ground. Seat height is measured from the saddle’s center to the crank’s center.
This chart gives us a good example of the inseam relative to the recommended bike seat height. The rule of thumb is to take your inseam and multiply it by 0.883 to get the correct saddle height from crank to seat.
Here’s our bike seat height calculator to fast-track this process if your exact inseam length isn’t included in the chart:
Bike Saddle Height Calculator
Inseam Length
Approximate Required Saddle Height
You can fine-tune your seat height based on your experience while riding. If you find that you’re getting pain at the rear of your knee, move the saddle slightly lower. If you’re getting pain at the front of your knee, try raising the saddle slightly.
To perfect your bike seat height, check out our In-Depth Guide to Bike Seat Height and Position here.
We also made this video below if you want to really dig deep into the science of seat height!
Understanding Saddle “Fore-Aft”
The saddle “fore-aft” is often known as the saddle setback. This is the second measurement we look at and is vital to getting an efficient pedal stroke.
The saddle fore-aft is measured horizontally from in line with the center of the crankset to the saddle’s nose.
The key to getting the saddle fore-aft correct doesn’t come from a measurement, on a chart and can be different for anyone depending on many factors such as the style of bike and seatpost design.
It’s normally about an inch or two, but you should set it for yourself immediately with the method below.
The way to find your saddle fore-aft is to sit on the bike, preferably against a wall or on a turbo trainer. Then, place your foot on the pedal at 3 o’clock with the ball of your foot next to the spindle.
Now, drop a plumb line (or a string with a weight tied to the end) down from just under the kneecap, and it should pass through the ball of your foot. If it doesn’t, move your saddle backward or forward until it does.
Understanding Reach (and “Handlebar Reach”)
When it comes to reach, there are two different concepts we can discuss.
Strictly speaking, “reach” is measured horizontally from in line with the center of the crankset to the center of the top of the head tube (see above).
This form of reach is decided by the frame size and design, and can’t be altered by the rider. When a bike manufacturer speaks about reach, this measurement is normally what they’re describing.
When a bike fitter talks about “reach”, however, they’re often describing handlebar reach.
In this sense, handlebar reach is the horizontal distance measured from in line with the center of the crankset to the handlebars.
Handlebar reach can be tailored by the rider, primarily by changing the stem length.
Moving the saddle forward or backward would effectively also change the handlebar reach, but we don’t recommend it as the saddle fore-aft should be set correctly as described above.
The stem is the component that connects the steerer tube to the handlebars. Mountain bike stems typically range from 40 mm to 80 mm in length, whereas road bike stems are generally between 80 mm and 130 mm.
Longer handlebar reach will make your riding position lower and more stretched out. This is more aerodynamic, but can become uncomfortable and put strain on your back, neck, and arms.
Shorter handlebar reach gives you a more upright riding position, increasing comfort at the expense of aerodynamics. An excessively short reach will leave you feeling cramped on the bike.
As a rule of thumb, your back should be at a 40 to 50-degree angle from horizontal while your hands are resting on the hoods, and a 30 to 40-degree angle with your hands in the drops.
There should also be around a 90-degree angle between your upper arm and torso while your hands are on the hoods.
Use this as your baseline, then adjust from here. Bear in mind that you’re trying to meet these guidelines through a combination of handlebar reach and handlebar height (see below). You can make adjustments to each until you find the balance that feels right.
If you’re relatively flexible and want to race competitively, you can be a little more aggressive with the riding position and opt for a slightly longer handlebar reach.
If you’re a casual rider or struggle with injuries, making the handlebar reach slightly shorter can increase your comfort.
Understanding Stack Height and Handlebar Height (With Chart)
Stack height is the vertical distance from the center of the crank to a point in line with the top of the head tube.
The relationship between stack and reach governs how upright your riding position is, amongst other things.
Here’s where you can see the stack come into play depending on the size of the bike. This chart focuses on what you typically find on a road bike. Bikes that require more control, such as mountain bikes, typically have a higher stack.
A higher stack will give a more comfortable riding position, and a lower stack typically offers aerodynamic benefits.
Handlebar height
Much like the reach, the stack cannot be changed on a bike – but we can adjust the handlebar height to change the rider’s position.
Stems come in all shapes and sizes, and it’s not just length where they differ, it’s also angle. Generally, a bike will come standard with a stem around 6-7 degrees but can come in all different angles, and some are adjustable.
An angled stem can be installed either way up, so that the angle is either raising or lowering the handlebar height. It’s a good idea to check out different stems online to see what’s available.
You can also adjust the number of spacers on the steerer tube below the stem to raise or lower the handlebars. If there are no spacers between the headset and the stem, this is known as a “slammed stem“.
Adjustments to handlebar height are closely related to changes to handlebar reach. Follow the same guidelines as when adjusting the reach, balancing and adjusting both the reach and height until you’ve found a fit that works.
If you’re chasing performance, keeping the handlebars lower will support aerodynamics. If you want comfort or more control, raising the handlebars will help.
Avoid raising the handlebars excessively, however. Doing so can significantly alter the bike’s geometry and handling, and feeling that you need to do so is normally a sign of a larger issue at play.
What counts as “excessive” depends on other factors, such as the size of your frame and the material of your steerer tube.
However, if you’re finding that you need more than 50 mm or so of spacers under the stem, or even – *gasp* – a steerer tube extender, then it’s probably a sign that either your frame is too small for you, or that you should switch to a style of bike with a more forgiving riding position such as a hybrid.
For carbon steerer tubes, the tolerance is lower. Manufacturers typically recommend no more than 30 mm of spacers for a carbon steerer tube, but it’s worth checking the website of your frame’s manufacturer to be sure.
What Crank Length Do I Need? (With Chart)
The crank length is the distance between the center of the crank and the point where the pedal attaches to the bike (the length of the crank arm).
Crank length can make a surprising amount of difference to how a bike feels to ride. The longer the crank arm, the more leverage you get, due to the principle of mechanical advantage. This increases the torque you can produce while pedaling.
Shorter crank lengths allow for less aggressive knee angles during the pedaling motion and can also make it easier to generate rapid cadences while sprinting, for example, but reduce your leverage.
Longer crank arms also increase the likelihood of pedal strikes while cornering. Shorter crank arms, combined with a frame with a relatively high bottom bracket, allow you to continue pedaling while cornering aggressively without risking a pedal strike triggering a crash.
This is a significant advantage for hectic racing in urban environments with regular sharp, 90-degree turns, as is common in criterium racing in US cities, for example.
If you want to know your crank length, typically, it is written on the crank arms themselves. If not, you can measure from the center of the crankset to the pedal insert.
Though this crank length chart can be used as a rough guide and reflects the crank arm lengths a bike of each size would typically be fitted with as standard, personal preference plays a significant role.
In my professional experience as a bike fitter, I have typically found that slightly shorter crank lengths enable the most comfortable and efficient pedaling motion for the majority of my clients.
For reference, I personally currently ride a size 56 road bike with 170 mm cranks because I find the shorter cranks significantly reduce the strain on my knees while pedaling, which is particularly important to me as an endurance bike racer.
When it comes to optimizing crank length, a longer crank arm might benefit you if you run a lower cadence and ride out of the saddle a lot. A shorter crank arm could be better if you ride at higher cadences and over long distances.
It really comes down to personal preference – or a professional bike fitter’s advice.
What Handlebar Width Should I Use? (With Chart)
The handlebar width can make a big difference when riding your bike. It changes how a bike handles, how aerodynamic the rider is, and the level of control you feel.
Wider handlebars improve control and provide a very stable feel to the ride, but increase your body’s frontal surface area while riding, increasing aerodynamic drag and slowing you down.
Narrower handlebars make your riding position more aerodynamic, but can make the handling feel twitchier.
They can also cause problems with shoulder tension and hand fatigue from the so-called “death grip” some riders adopt with narrow handlebars. This is particularly relevant to women’s bikes, which tend to come with relatively narrow handlebars for their frame size.
Bikes typically come equipped with different-sized handlebars depending on the frame size. The larger the frame, the wider the handlebars. The flat handlebars on mountain bikes also tend to be wider than the drop handlebars on road bikes.
Here’s a reference chart for the handlebar widths that would typically be fitted to road bikes of various sizes as standard if bought new.
The typical advice you’ll hear from a bike fitter is that the handlebar width should match your shoulder width. We recommend measuring from shoulder blade to shoulder blade to find the handlebar measurement to use as your starting point.
However, personal preference again plays a large part. Beginner riders may benefit from the extra confidence and stability afforded by wider handlebars, while experienced cyclists and racers can handle narrower bars to reap the aerodynamic rewards.
Tadej Pogačar, for example, used 36 cm ENVE Aero handlebars throughout the 2023 Tour de France, despite riding a size 54 frame (suggesting a typical handlebar width of 42 cm).
Over all the years I have been cycling, I have experimented with a wide range of handlebar widths.
I personally tend to opt for a size smaller than would be standard for me because I like the handling feel and I appreciate the aerodynamic benefits for ultra-distance racing, but I know experienced riders who choose wider handlebars, purely based on personal preference.
Getting a feel for a few different handlebar widths goes a long way to knowing where you should be.
Overall Bike Fitting Chart
So as you can tell, it’s all well and good getting the right-sized bike, but when it comes to fit, there’s much more to consider.
You can completely change how a bike rides and performs by changing the fit and swapping out or adjusting different components.
We’ve created an overall bike fitting chart below – but it’s vital to recognize that this is purely for reference.
There is no such thing as a “one-size-fits-all” approach to a bike fit. Very few of us are a close match for each aspect of a “typical” body shape for our height, and so different elements of the bike fit will diverge from this chart.
However, you can use this chart as a ball-park reference guide to typical measurements and sizings for different elements of a bike fit for riders and frames of different sizes.
