The cranks on a BMX bike are similar to that of any bike, however BMX cranks are only built to run single speed so they can only drive one chainring unlike mountain or road bikes.
The first variant on cranks is whether there Right Hand Drive or Left Hand Drive. Traditionally all bikes are right hand drive however in BMX there are benefits to running left hand drive. With BMX bikes now running smaller gearing like 25-9, depending on whether you run pegs or not this may or may not be applicable for you. For example if you run your pegs on the left then right hand drive is ideal for you, as your drive train is on the opposite side of your bike to your pegs. But if you run your pegs on the right the opposite would apply, Left hand drive would be better, again keeping the drive train on the opposite side of the bike to your pegs. These days a lot of BMX Cranks are designed to cater for both. However its really worth considering your options regarding drive before buying a new set of crank.
The second variant on cranks is Crank Arm Length, this is normally displayed in millimetres. Traditionally BMX cranks are 175mm however shorter cranks like 170mm, 165mm and even 160mm have become popular with peg users as BMX frames have got a lot shorter rear ends these days. Longer cranks are also available and are a lot more popular with BMX racers who seek a greater leverage.
Finally the last variant is Axle Size. There are currently 3 different axle sizes in use. 19mm, 22mm and 24mm axle cranks can all be regularly found on our site. The only important part of this is what Bottom Bracket you'll need to run the cranks in your bike. If you have 19mm cranks you'll need a 19mm Bottom Bracket, if you have 22mm cranks you'll need a 22mm Bottom Bracket and 24mm you'll need a 24mm Bottom Bracket. Some cranks are supplied with bottom brackets today, however the majority or cranks sets are still supplied as cranks only. Make sure you have a compatible Bottom Bracket for the cranks you wish to buy, if you don't simply head to the bottom bracket page on our website and buy the which ever type you require.
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