Race or Freestyle: sizing BMX bikes is important

Sizing a BMX bike, for Race or Park.

Race BMX:

Racing is all about acceleration, speed and being able to handle jumps and berms. Proper sizing at its most basic is going to be safer for the rider. Sizing will also ensure the kid has fun and has a fair chance to do well.

As you can imagine, an 8 year old with a 30 lb. bike is going to struggle keeping up to a kid on a 15lb bike. Now imagine the cranks are super long on that 30lb bike, the frame is huge, the handlebars are huge, tires don't roll easily and the brakes barely work... This is essentially sticking your kid on a non-sized bike.

As mentioned 2 sentences ago. Frame length, crank length, weight, tires, bearing quality, handlebar height and width: these are the factors of bike sizing.

 

BMX Freestyle.

Freestyle is all about the rider being able to overpower the bike. Bike size is critical. At the most basic: rider standing on level pedals should be standing with arms pointed down, not forward to the handlebars. Beyond this, frame length can be important: shorter frame for techy/spinny tricks, longer frame for going big and high-speed / trails type riding.

 

Rider Size

Race BMX Bike Size

Freestyle BMX Size

<4'4" Micro Mini 12" Wheel
4'2" to 4'6" Mini BMX 12" Wheel / Pitboss 16"
4'6" to 5'1" Junior BMX 16" or 18"
5'0" to 5'4" Expert BMX 18" to 20" with <20" Top Tube
5'2" to 5'6" Expert XL 20" to 20.5" Top Tube
5'3" to 5'8" Pro (20.5" TT) 20.5" TT (up to 21")
5'7" to 6'1" XL (21" TT) 20.5" to 21.25"
5'11 > XL, XXL 20.75" >