BMX Bike

A BMX bike is an off-road sport bicycle used for racing and stunt riding. BMX means bicycle motocross. Though originally denoting a bicycle intended for BMX Racing, the term "BMX bike" is now used to encompass race bikes, as well as those used for the dirt, vert, park, street, flatland and BMX freestyle disciplines of BMX. BMX frames are made of various types of steel, and (largely in the racing category) aluminum. Cheaper, low end bikes are usually made of steel. High range bikes are mostly chromoly or high tensile steel, although the latter is noticeably heavier with respect to strength. High-performance BMX bikes use lightweight 4130 chromoly, or generation 3 chromoly.
Most freestyle, street, and park BMX bikes, the wheels have 36 spokes. Race bike wheels are also usually 36 spokes, but wheels for the smallest racers, sometimes as young as three years old, can be built with 18 or 28 spokes. More aggressive riders may opt for wheels with a spoke count of up to 48 spokes, however hub and wheel combinations for this are becoming difficult to source.

BMX Tricks and tips :

Scuffing - Using feet on the tires to maintain speed, to brake, or to stall the bike.

Hitchhiker - When the rider is rolling with feet on the front pegs and holding the back tire up so that the handlebars are just skimming the ground.

Dumptruck - When the rider rides on the back wheel facing backwards, with one foot on the peg and the other foot scuffing the tire in the direction the rider is facing.

Steamroller - When a rider rolls forward with one foot on a front peg and the other foot maintaining balance while one hand holds the handlebar and the other hand holds the seat with the frame of the bike in front of the rider.

Whiplash - When a rider rolls forward and does a tailwhip while standing on the front pegs.

Because of the nasty spills riders can encounter in BMX, riders wear helmets, long-sleeved jerseys and pants, and gloves. The long-sleeves are intended to provide protection from abrasion in case of crashes. The helmets -- unlike regular cycling helmets -- feature full masks to protect the rider's entire face. Riders can also wear elbow and knee pads as well as chest protectors and shinguards, but those are less common in high-level competitions like the Olympics.