Guide for Assembling a Complete BMX

When purchasing a complete BMX bike, you'll find most parts are pre-assembled. However, to fit it into a manageable box size, the handlebars, pedals, and front wheel are detached.

Putting together a complete BMX bike is straightforward if you adhere to the instructions in the video along with the steps specified below. Your new complete BMX will be ready in no time!

Assembling the bike is a great opportunity to familiarize yourself with it. As a passionate BMX enthusiast, there’s nothing more satisfying than getting your new bike ready with some TLC before your first ride.

What Tools Are Necessary for Assembling a Complete BMX Bike?

Getting started requires only a few tools.

Allen keys
Wrenches
Open-ended 15 mm wrench for pedals
Air pump

Check out our range of BMX Tools — We have all you need!

Step-by-Step Guide - Unboxing and Assembly of a Complete BMX

Begin by removing all plastic and foam, and ensure that nothing is missing as you unpack everything.

Starting the assembly process

Apply grease to the pedal bolts.
Determine which pedals are left and right.
Screw the right pedal clockwise - tighten using a wrench.
Screw the left pedal counterclockwise - fully secure it with a wrench.
Loosen the bolts on the stem.
Detach the stem faceplate.
Apply grease on the stem bolts.
Attach the handlebar.
Position the faceplate over the stem, ensuring the knurled portion of the handlebar is centred in the stem.
Tighten the stem bolts in a cross pattern—at this stage, do not fully secure the faceplate.
Loosen the top cap/compression bolt with an Allen key.
Align the handlebars with the fork.

You are now ready to attach the front wheel:

Loosen the front axle nuts almost entirely to fit the fork dropouts.
Hand-tighten the nuts.
Secure the nuts fully with a wrench.
Insert the BMX seat into the seat tube; consider greasing the clamping area inside for easier seat post removal in the future.
Tighten the seat clamp using an Allen key.

Once the seat is in place, you can adjust the handlebars and fork alignment while sitting on the bike, allowing you to make perfect adjustments more easily:

Align the handlebar with the fork—the front wheel will guide you.
Secure the top cap/compression bolt using an Allen key.
Final tightening of the stem should use a cross pattern, meaning you always tighten the bolt diagonally across from the last one you tightened.
Ensure there's a uniform gap between the stem faceplate and the stem itself—it's essential that the faceplate is tightened evenly.

Before you head out to ride, ensure the following:

Check the chain - if it moves more than 2 centimetres, it’s too loose—this can be adjusted by loosening the wheel and pulling it back until the chain is properly tight.
Ensure that all nuts and bolts are securely tightened.
Inflate the tires to the recommended pressure (indicated in PSI on the side of the tire).
Unscrew the valve cap and attach the pump.
Inflate the tire and replace the valve cap.
Repeat on the other wheel.
You’re now ready to ride!

Explore our comprehensive range of complete BMX Bikes.

If you need more detailed guidance for brake installation, see: How to Mount a BMX Brake.