Mongoose Legion L20 Freestyle BMX Bike Review

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Anyone researching bikes and looking for quality models will likely have come across the Mongoose brand. They are one of the top bike manufacturers in the industry.

So the hopes are high that their Mongoose Legion L20 Freestyle BMX Bike will live up to their reputation.

Mongoose Legion L20 Freestyle BMX Bike


After Skip Hess developed a durable wheel made from cast-magnesium for BMX bikes in his garage, Mongoose came into existence.

Mongoose has become one of the most recognizable names worldwide for high-quality bikes from that single wheel.

In particular, their mountain and BMX bikes are highly regarded, and the Legion L20 is one of no fewer than 29 different BMX bikes that they produce.

Legion is a range with 9 other models, and the L20 is one that uses 20-inch wheels; it has a choice of 4 colors.

Who Is This Product For?

The Mongoose Legion L20 is a BMX bike, which will not appeal to those looking for a bike they can commute on. Instead, fans of BMX, as well as those looking for a bike that can be used for racing, agility, and track biking, will most certainly like it.

The size of the L20 is for those who are between 4 feet 4 inches and 5 feet. With those heights, the bike is suitable for youths as well as smaller adults. It would also make a great beginner BMX bike for those wishing to learn.

What’s Included?

As you may know, most bikes require some degree of assembly once they have been taken out of the box. The Legion L20 is no different, although, in this case, there is not as much assembly required as you might find with other bikes.

You will find the bike’s frame in the box, which will have the chain assembly and the rear wheel already assembled.

Also, the front wheel, the handlebars, and the pedals will be all in the box, and it is these items you will attach to the bike to fully assemble it.

Overview of Features

BMX bikes usually need to stand up to some fairly rough treatment, given the jumps and tricks that many users try. So the fact that the L20 has a strong steel frame augurs well for its durability.

The drivetrain has a single-piece forged steel crank with an alloy chainring, which should ensure that no matter how robustly it is being pedaled, it will keep driving that rear wheel for years.

The handlebar assembly is also made from durable steel, and it houses the single brake handle. Note that one feature of the L20 is that the brake mounts are removable.

The 20-inch wheels have single-wall aluminum rims and tires, which are 2.3-inches wide to provide superb grip and traction.

Finally, we should mention that you have a choice of 12 colors, which include black, gold, copper, green, silver, and maroon.

How to Use It

The Legion L20 has one of the easiest bike assemblies you could wish for, but that does not exclude the option, if you prefer, to have your local bike shop assemble it for you.

For those who want to assemble it themselves, the time it will take should be between 20 and 30 minutes; however, do not rush it just to finish quickly.

Follow the assembly instructions carefully and ensure the bike is safe to use.

You will need basic tools such as Allen keys, an adjustable wrench, pliers, and a Phillips screwdriver.


  • Durable steel frame
  • Suitable for youths and beginners
  • Very easy to assemble
  • Aluminum brakes
  • Forged steel drive chain


  • Owner’s manual is generic
  • Chain tension can be too tight


Mongoose Legion L16 Freestyle BMX Bike


If you love the Mongoose brand and its BMX bikes but need one for someone a bit smaller in height, such as a child who is a little bit younger, you might want to check out the Mongoose Legion L16 Freestyle BMX Bike.

This obviously has the Mongoose name, so you can expect the same high-quality level that the L20 has. With 16-inch instead of 20-inch wheels, younger and smaller children can use it, plus the L16 comes in a choice of 7 different colors.


Whether you are buying this bike for a youth or a beginner to BMX bikes, you can rest assured that the Mongoose name means that it has quality parts and workmanship. These combine to make the Legion L20 a top-quality BMX bike that offers superb value for money.

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