It can be difficult to pick out the best bike for you: there are so many factors to consider! But none of the other ones matter if your bike’s frame isn’t the right size.
So how can you tell if the bike you’re riding is just too small for you?
A bike frame that’s too small will feel twitchy and unstable at higher speeds. It will also force you into a cramped riding position which will feel very uncomfortable on longer rides. That cramped position may also prevent you from operating the bike normally and could impede safe handling.
So what should you look for when choosing a new bike to make sure it’s not too small?
You’ll find all the information you need below!
3 Signs Your Bike is Too Small
1. You Don’t Fit in the Cockpit
The area between the bike handlebars and seat is called the cockpit: just like a plane, it’s the place from which you (the “pilot”) operate and control the bike. It’s hard to operate your bike if you have trouble fitting in the cockpit though.
So how do you tell if you’re a little too cramped in the cockpit?
Do your feet stay clear of the front wheel when making turns? Sit on your seat, rotate your pedals to the 3 and 9 o’clock positions, and place a foot on the front pedal. Then rotate your handlebars through a full range of motion. If your front wheel hits your toes as it swings, this is a clear sign you need a bigger frame.
A foot strike on your front wheel could definitely lead to a crash and, especially in the middle of a turn, it could throw you right off your bike!
Do your knees hit the handlebars while pedaling? If so, it’s also time for a bigger bike. Though your bike would have to be several sizes too small for this to occur, it’s still possible. If your bike has a dropper post, make sure your knees clear the bars at all seat heights.
Speaking of seat height…
Can you get your seat high enough? Your seat is at the correct height if you have just a bit of knee bend with your foot on the pedal in the 6 o’clock position. If you can’t extend your seat post high enough to achieve this position, your seat post is too short. This is likely because the seat tube is too short and can’t hold a longer seat post.
Larger bike frames have larger seat tubes and can hold longer seat posts: another sign you’ll need to upgrade to a larger bike.
2. Riding Always Makes You Sore
Let’s face it…there are a lot of ways biking can make you sore. From crashes, to falls, to pedal strikes to the shins (ouch!), biking can be a painful activity sometimes. But if every ride has your joints aching, your bike’s size may be a contributing factor.
Having your bike properly set up for your anatomy is very important for keeping your muscles and joints (relatively) pain-free. A bike that’s too small will place you into an unnatural, unnecessarily cramped riding position. The more miles you put in, the more you’ll notice the negative effects.
A cramped riding position doesn’t allow you to fully extend your hips, knees, arms, upper back and neck. The affected muscles will get tight over time if they’re prevented from working through a normal range of motion. This can lead to a host of other issues off the bike, including chronic joint pain, poor posture and muscular imbalances.
If at the end of every ride, you feel like you’ve just gotten off a trans-Atlantic flight spent in “economy” (not even “economy plus” with the extra leg room), a bigger bike frame may be the solution to your problems.
3. Your Bike Handles Poorly
If you can’t get into the right riding position because your bike is too small, it’s going to negatively impact the way your bike handles.
Most of the time, you want your body weight evenly distributed on your bike, with the ability to shift forward or back depending on the terrain. A bike that’s too small will bias your weight toward the front end of the bike.
The cramped riding position will also make it difficult to shift your body weight rearward when you need to, such as when braking hard or going downhill.
When braking hard or tackling steep terrain, shifting your body weight over the rear wheel will help you maintain control and prevent an over-the-bars (OTB) occurrence. With more of your weight over the front end, a bike that’s too small will make it much harder to stay in control if you were to stop suddenly or hit an obstacle.
A bike that’s too small for you will also tend to feel twitchy and unstable, especially at higher speeds. Riding a bike that gets squirrely when going fast is certainly not confidence-inspiring.
Now I know some of you might be thinking: “How can I tell whether my bike is handling poorly because it’s too small, or because I’m just not very good at riding fast, steep terrain?”
That’s a valid question.
Practice will certainly make you better at steep, technical terrain. But so will having the right sized bike. Try renting a larger frame size, or riding a friend’s larger bike on your favorite road or trail loop. You’ll immediately be able to tell if it makes a difference.
How to Choose the Right Bike Frame Size
Bike frames are first and foremost designed around rider height, so this is the first thing to look for when choosing a new bike. Each frame size will fit a small range of heights, so find the one you fall within and there’s a great chance it will be the right size for you.
Why You Might WANT to Choose a Smaller Bike
Your height will point you in the right direction, but it isn’t the only factor determining which size bike is right for you.
Because many people fall directly in between two frame sizes.
So are you supposed to size up or down? Well, it really depends on the type of riding you do and how you want your bike to perform.
When you’re shopping for a new bike and comparing frame sizes, you’ll see a lot of measurements. While they all mean something, some are more important to understand than others. Let’s define these here:
Reach is the horizontal distance measured from the bottom bracket to the head tube (or roughly from the center of the seat to the center of the handlebars). Reach will indicate how far forward you’ll need to lean to reach the handlebars. A shorter reach will provide a more upright riding position, while a longer reach will provide a more aggressive, forward-leaning position.
If you have a relatively short torso, a bike with a shorter reach will be more comfortable (you won’t need to lean over as far to reach the handlebars). If you lack flexibility and mobility in your hips and back, a more upright riding position may also serve you better.
Wheelbase is the length measured from the front wheel axle to the rear wheel axle. A longer wheelbase will result in a more stable (but less responsive) bike, while a shorter wheelbase will give you a more responsive (but twitchy) bike.
If you like to ride fast in mostly open terrain, you may want to size up to a bike with a longer wheelbase. But if your terrain is tight and full of trees or other obstacles waiting to grab your handlebars, or you want a bike that’s easier to throw around and get into the air on jumps, you may prefer sizing down to a bike with a shorter wheelbase.
Standover height is measured from the ground to the point on the top tube where it intersects with the bottom bracket. In other words, if you were to mount your bike and then take your feet off the pedals and place them on the ground, the position right between your legs would be where the standover height is measured.
Standover height usually doesn’t change much between frame sizes…but sometimes it does. If you’re a taller rider but have short legs, you may just not have enough clearance between yourself and the top tube should you slip off the pedals. And this isn’t a fun situation. Be sure to check a few different frame sizes to see which gives you enough room to bail if needed.
Seat Tube Length
Seat tube length is simply the length of the seat tube. Pretty self-explanatory, but why does it matter?
Because that’s where the seatpost goes!
Your seatpost inserts into the seat tube, allowing you to adjust your seat height (or range of heights if you have a dropper post). Seat height is very important for getting in the proper riding position. Your seat tube determines how long of a seatpost you can install. A longer seatpost means a greater range of possible seat heights.
A short seat tube will limit how far down you can slam your seat. If you’re a taller rider, this will negatively impact your performance on steep descents, as your seat could get in the way.
A long seat tube may provide too much seatpost travel, not something you need if you’re a shorter rider…you don’t want to be sitting on the seat and your feet can’t even reach the pedals! If you can’t take full advantage of the entire range of travel for your seatpost because it’s just too long and puts you up too high, you may want to go down a size.
Check out this video for a visual representation of these (and other) important measurements, so you make sure to get the right size bike for you!
These four measurements become especially helpful when comparing different bike brands, where one company’s Size Medium may be another company’s Size Large.
So if you’re considering a switch to a different bike brand, instead of simply choosing a larger frame size, record these four measurements on your own bike and compare them against the measurements from other bike options. You might end up choosing the exact same frame size in the end, but the way your new bike feels could be very different!