Why Are BMX Bikes So Small? 5 Reasons Explained!

Have you wanted to buy your next bike, but all that revolves around your mind is a BMX bike. You then dive deeper in your search, but you wonder, why are BMX bikes so small?

BMX bikes are small because they have small wheels, compact sprockets, smaller cranks, and low seats, and they were initially meant for kids. The smaller sizes reduce the overall bike weight making them the best performers in stunts and tricks.

Overall, the smaller size of BMX bikes comes with several advantages that will have a look at later. This guide will explain why BMX bikes are so small and give you a sizing guide to use when buying your next BMX bike.

As a bonus, I will also answer some questions about the topic.

Let’s get started!

5 Reasons Why BMX Bikes Are So Small

Below are five reasons why BMX bikes are too small:

1. They Have Small Wheels

BMX bikes indeed come with smaller wheels. Even some as small as 15 – 16 inches. However, the most common BMX bike comes in 20-inch wheels. That’s the general and the first reason why BMX bikes are so small.

Though they may look odd, especially if you are a tall adult, their smaller wheel size comes with the following advantages:

  • Faster speed and acceleration because of reduced weight
  • Easier to maneuver
  • More portable

2. They Have Small Sprockets

BMX bikes come with small, compact sprockets, which come with several advantages. They include:

  • The chain won’t break easily
  • The bike is sturdier and less bendable

That means that you remain at the par of your performance. Furthermore, smaller sprockets have less weight, meaning you will have an overall lighter bike, which will be an advantage when performing the tricks.

Are BMX Bikes Supposed to Be Small

3. They Have Small Cranks 

Usually, BMX bikes come with a smaller crank length of around 145mm – 190mm. However, most freestyle riders prefer a crank of about 165mm.

The shorter the crank, the better the ground clearance, which comes in handy when performing tricks. Furthermore, the shorter cranks will also translate to a lighter bike, and it will also mean that the pedals will be much closer to the center, and you will likely catch them easily when thumping.

Short cranks are also ideal when taking the bike on flatland and common in racer BMX. They make it easy to ride a race BMX faster.

4. They Have Low Seats

As you already know, BMX bikes come with low seats that make them small. But the low seat gives you better clearance for maneuverability while performing stunts and tricks.

The lower seats also make pedaling while standing much easier and allow you to quickly grab and access the seat with legs when doing the tricks.

5. Were First Meant for Kids

Initially, BMX bikes were meant for kids in the 6-17-years age bracket. However, they slowly gained popularity, which saw more adults become fonder of them, but unfortunately, the design hasn’t changed much – so the bikes remain small, which is one primary reason why BMX bikes are so small.

On another note, BMX bikes come with fewer components, unlike other bikes, making them more kid-friendly as they are easier to maneuver and control.

The good news is that the manufacturer now makes several wheels and frame sizes to cater to adult needs.

However, they also allow room for customization to suit your individual needs, especially if you are tall.

Advantages of BMX Bikes Being Small

Below are the benefits of the smaller BMX size:

a. They Are Lightweight

Generally, you will find BMX bikes weighing between 10 – 28 pounds, making them lightweight. Their lightweight is because they do not have many moving parts, unlike other bike types.

The bike’s lesser weight will help you control and maneuver the cycle. Usually, they are lightweight and strongly built to help perform stunts and tricks hassle-free.

They usually have either aluminum or Chromoly steel frames. The aluminum options are lighter, while the steel options weigh slightly more.

Are BMX Bikes Still Popular

b. Excels Well in High-Risk Tricks and Stunts

Ask Pro BMX riders, and they will tell you that the smaller the bike, the higher it will go in the air when doing high-risk stunts.

So, with that in mind, BMX bicycles are fantastic in handling bigger jumps than other bike models, which explains why BMX is an Olympic sport.

Overall, if you are looking for a BMX bike that can give you a 360-degree spin or do giant leaps, the Mongoose Legion Mag Freestyle BMX will perform exceedingly.

This 20-inch freestyle BMX comes in a hi-ten steel frame making it robust to perform high-risk maneuvers and stunts. It is an excellent pick for both beginners and advanced cyclists.

c. Makes Them More Mobile

You will agree that it’s easier to move around with a smaller bike than with a bulkier one. Right? BMX bikes allow you to carry them anywhere as they are more portable due to their lightweight.

And due to their small size, they are also easier to maneuver and can take all the heavy impacts on the road.

A more maneuverable BMX will give you an easier time while making flatland tricks and aerial stunts seamless and allows you to make the turns easily, especially on the wet ground

d. Small Bikes Are Fast

Because BMX bicycles are small and lightweight, they also have smaller wheels with fewer spokes.

This helps in creating less friction, unlike larger wheels. That’s also why many Olympic BMX riders use the options with smaller wheels.

Again, you will also need a BMX bike with smaller wheels when riding in heavy traffic. That is because you may be required to make sudden stops as it gives you fast acceleration and power.

Is a 20 BMX Too Small

What Size Are BMX Bikes?

One important consideration when it comes to buying any bike is the size. BMX manufacturers understand this well, and that’s why they have eight different bike sizes in their arsenal.

If you are a young kid and you measure below 5’4¨ inches, you should pick the small size BMX in the category of micro, mini, junior, or expert, while if your height goes beyond 5’4¨ inches, you should consider a bike size pro, pro-XL, pro-XXL, pro-XXX or a cruiser BMX.

Here’s a table summary that you can use when buying a BMX bike:

Bike SizeFrame Size (Inches)Wheel Size ( Inches)
Micro 15 – 16¨16¨
Mini 16 – 17¨18¨
Junior 17 – 18.5¨20¨
Expert 18.5 – 19.5¨20¨
Pro 20 – 20.5¨20¨
Pro XL20.7 – 21¨22¨
Pro XXL21.5 – 22¨24¨
Pro XXX22¨24¨
Cruiser 21.5 – 21.75¨24¨

People Also Ask

Are BMX Bikes Supposed to Be Small?

BMX bicycles were first designed for kids, and that’s why they assume a smaller geometry. Over time, however, they have become popular among adults. However, their small size makes them more maneuverable, lightweight, and easy to ride, thus suitable for freestyling and racing.

Why Are Olympic BMX Bikes So Small?

The reason Olympic BMX bicycles are small is to perform bigger jumps. As stated earlier, the smaller the bike, the bigger the jump. So, Olympic BMX riders understand this, and that’s why they usually go for the smaller BMX options.

On top, the smaller the bike, the lighter it will be, and this is an advantage when landing after a big jump.

Are BMX Bikes Still Popular?

BMX sport has been popular in the USA and globally since the 80s. And following its inclusion into the Olympics, BMX sport has never been more popular than it is. Both freestyle and race BMX sports are popular globally.

Furthermore, BMX bikes are generally affordable, encouraging more people to buy them. You can get so many BMX bikes under $500 (Check on Amazon), making them affordable by most buyers, thus popular.

Is a 20 BMX Too Small?

No! 20-inch BMX bikes are the average BMX size. Most riders who are 5’3¨ inches tall and weigh between 110 – 150 pounds can comfortably ride a 20-inch BMX bike. But still, some of these bikes can accommodate adults.

Why Are BMX Bikes So Expensive?

Ideally, BMX bicycles are not expensive as you can get most options under $500. There are, however, a few high-end options, which are costly because of their build quality. The manufacturers invest in high-end specs and advanced technologies, making the bikes expensive.

Besides, BMX bikes are built with responsiveness, can take on rough usage, and are lightweight. That significantly influences their prices.   

What Does BMX Stand for?

BMX is a short form of Bicycle Motocross. Actually, BMX is an Olympic cycling sport. Essentially, we’ve freestyle BMX, where riders perform stunts and high-risk jumps, and racing BMX, where riders compete on tracks and dirt paths.


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Why Are BMX Bikes So Small? Closing Remarks!

There, you have it! The reasons that make BMX bikes small. As seen, they are small because they have smaller wheels, short sprockets, and cranks, lower seats, and they were initially designed for kids.

However, you should not be fooled by their small sizes, as you can be sure to find an adult BMX bike that suits you.