Race BMXs are different from their street and skatepark cousins; they’re usually made from lightweight but strong aluminium but at the top end full carbon fibre frames are now making an appearance. Rather than being designed to do tricks on, race bikes are built for speed!
Race BMX bikes come in two forms; those with 20” diameter wheels (known as 20” or 20’s) and those with 24” wheels (known as Cruisers.) Far from being too small or for kids (an adult on a BMX does get a lot of funny looks from non-cyclists!) the small wheels make the bike lightning fast and extremely manoeuvrable. It’s their compact size that makes race BMX bikes agile on the demanding tracks where competitions are held.
Unlike mountain bikes where the suspension and tyres do a lot of the work getting over obstacles, on a BMX it is all about the rider. They may have seats but riders don’t sit down to pedal (the seat gets used when the rider is balancing on the start gate, or most often, when they’re chatting between laps!)
Cruisers are more stable than their 20” counterparts and so are a little easier to ride.
Getting the right size can be confusing, when people discuss size of a race BMX, they are generally referring to the length of the bike rather than its height. A road or mountain bike size lists the length of the seat tube, on a BMX the size given refers to the length of the top tube. Taller riders will have longer bikes. It’s easier to think of stage, rather than age for sizing. A tall 7 year old may need the same bike as a short 9 year old!
Unfortunately there isn’t an industry standard on sizing; one brand’s Pro XL may have a 21” top tube, another’s it may be 21.25” and believe it or not, size does matter!
Here’s a rough guide;
The best bet for sizing is to come to a club session and try bikes for size!