How to Change Freewheels on a BMX Bike

The size of your freewheel determines how quickly the pedals will spin when riding fakie, an essential part of being comfortable with your bike.

Changing the freewheel on your BMX bike allows you to customize the gear ratio between the front chain ring and the rear sprocket. This allows the rider to change how much (or how little) effort it takes to turn the pedals and how quickly they turn at speed and when riding fakie. The gear ratio is an often-overlooked but very important part of how you ride your bike. Get you setup dialed in to your riding style by changing the freewheel on your bike at home.

Things You'll Need

• Basic wrench set
• New freewheel
• Freewheel remover

Instructions

1. Set the bike on its handlebars and seat. Using a combination or adjustable wrench, loosen the axle nuts of the rear wheel. If you have pegs installed, you will have to remove those first.

2. Pull the wheel out of the frame. Let the chain hang from the front chain ring. Set the wheel freewheel side up on a work bench or desk. Set a freewheel tool (usually a round metal object with four prongs on it. Be sure you get the right tool for your freewheel) in place on the freewheel and thread an axle nut onto the axle to hold the tool in place.

3. Use a combination or adjustable wrench to turn the freewheel tool counterclockwise. The freewheel will begin to twist away from the hub. Remove the axle nut and pull the freewheel off of the wheel.

4. Thread the new freewheel onto the hub as far as possible by hand. Set the freewheel tool and axle nut in place and use a combination or adjustable wrench to tighten the freewheel to the hub. Remove the freewheel tool from the wheel.

5. Set the wheel back into the dropouts of the bike and wrap the chain around the new freewheel. Pull the wheel away from the crank to tighten the chain and tighten down the axle nuts using a combination or adjustable wrench. Reinstall any pegs or other accessories that were removed previously.

6. Take the bike for a test ride to try out your new gear ratio. You should notice that it is either easier (if you installed a larger freewheel) or harder (if you installed a smaller one) to pedal the bike, and that the speed of the pedals when riding fakie has changed, as well.

References

• The Big Blue Book Of Bicycle Repair; 2009; Park Tool