Condensed Answer: A standard BMX can be used as a normal bike by children and short adults. It’s also possible to make a BMX more comfortable for a taller person by installing an extra-long seat post.
That said, BMXs are not designed for standard commuting and have other downsides besides the small frames that make them an illogical choice in many cases.
The Downsides Of Using a BMX As a Commuter
- Seated Pedaling = Inefficient and Uncomfortable
The main problem with using BMXs as normal bikes is that the saddle sits too low and most adult riders cannot fully extend their knees. Consequently, pedaling in a seated position becomes uncomfortable, unbalanced, and inefficient.
There are two possible solutions to this problem:
a. Buy a larger BMX (There are 22″, 24″ and 26″ options that are less popular than the standard 20″ size but still present on the market.)
b. Buy an extra long seat post
This is the most obvious approach. A longer seat post would increase the distance between the bottom bracket and the saddle and make it possible to pedal more efficiently without replacing the entire bicycle.
It’s also worth mentioning that there are BMX seat post extenders. Those represent tubes that insert into the seat tube. Once the extender is inserted, then the original seat post slides in it.
Note: The video above explains the principle behind BMX seat post extenders.
- Low Handlebars
The seat post of a BMX can be elevated, but the handlebars can’t be. Even though BMX bikes use the tallest handlebars, in some cases the height could be insufficient if the rider is tall. The result is an uncomfortable position/improper fit that places unnecessary stress on the joints.
For the sake of simplicity and robustness, BMX bikes have a single-speed drivetrain. This property makes the bike easier to maintain and less susceptible to external damage since there are no derailleurs to worry about. However, the lack of gears limits the bike’s top speed and makes climbing harder.
In some cases, it will be necessary to get out of the saddle and exert a lot of effort. The lack of gears makes BMX bikes less than ideal commuters for hilly terrain and long distances.
- Incompatible With Many Commuting Accessories
BMX bikes are built for the performance of various stunts. Consequently, they lack the necessary mounts for the installation of standard commuting accessories such as racks and fenders.
If you plan on doing long commutes in all kinds of weather, this will be highly problematic. That said, there are creative ways to overcome those issues. The question is why bother and not get a proper commuter instead?
Freestyle BMX bikes have low gearing (smaller chainrings are chosen for extra clearance during tricks) and cannot offer a high top speed.
Racing BMX bikes have a much higher gear, but they are still slower than larger bikes due to the small wheels.
If two bikes have the same top gear, then the bike with the larger wheels would have a higher top speed because each rotation of the rear wheel results in greater travel. Or in other words, the larger the wheel is, the more the bike moves forward per 1 spin.
- Subpar or Complete Absence of Brakes
The vast majority of BMX bikes have either a rear brake or no brakes at all. Those setups facilitate the performance of tricks such as bar spin but do not offer adequate braking power when the bike is used for commuting.
The rear brake is a lot less powerful than the front brake. During braking, there’s a weight shift to the front of the bike. As a result, the rear wheel loses traction while the front one gains traction. Hence why it’s so easy to skid the rear wheel. The extra traction of the front wheel makes the front brake much more efficient.
For that reason, it’s recommended to install a front brake if you’re going to commute on a BMX. It will prevent you from performing bar spins unless you use it in conjunction with a gyro system, but the extra stopping power will be very helpful for commuting.
It’s also worth mentioning that BMX bikes are not designed for disc brakes and use U-brakes or V-brakes. Rim brakes are very effective in dry but lose their edge in wet conditions because the rim gets contaminated. The initial contact between the brake shoes and the rim serves to clear the rim of contamination and debris. For that reason, braking in the wet is slow and noisier.
In different, disc brake calipers grab a rotor mounted to the hub. The rotor is further away from the tire than the rim and doesn’t suffer the same degree of contamination. Consequently, disc brakes offer supreme braking power even in wet conditions.
The Advantages of Using a BMX as a Normal Bike
Standard BMXs are some of the smallest and most compact rigid bikes out there. As such they’re easy to store in an apartment and transport via an elevator. Also, they fit in a standard car quite easily in comparison to full-size bicycles.
- Simplicity & Robustness
BMXs are built to endure a lot of punishment. A quality unit sees commuting as an easy task and offers decades of faithful service.
Additionally, BMXs are very easy to maintain as they have no suspension and use a single-speed drivetrain with a robust chain.
- One Bike For Everything
If you already have a BMX for stunts and want to use it for short errands in the neighborhood, the bike will serve you well, and you won’t have to purchase and maintain another one.
- Fast Acceleration
Small wheels equal faster acceleration because it’s easier to get them to a high RPM (rotations per minute). This property is beneficial in urban settings when agility and fast reaction times are of the essence.
Alternatives to a BMX
If you want a BMX for its compactness, the most logical alternative to it would be a folding bike. Just like BMXs, folding bikes use small wheels (18″-22″) and accelerate fast. Another bonus of folding bikes is that they have an extremely small profile and can be taken on public buses and trains with no issues.
Of course, a folding bike cannot be used for the performance of tricks because it’s heavy and has the wrong geometry for such riding.
If you don’t care for a folding bike, you can look at the so-called mini velos. Those are road bikes with adult-size frames and small wheels. Just like a BMX, they have 20″ wheels. Their advantage is that the frame and its geometry make the bike comfortable for taller people while offering a lot of speed. Many models come with disc brakes too.
A mini velo would be a much more efficient commuter than a BMX while having a similar profile. The catch is that they’re not very popular (small pool to choose from) and can’t be used for stunts.