BMX Bike

A BMX bike is the name of a popular bicycle used for both casual riding and sport, and designed mainly for dirt and motocross cycling. "BMX" is the usual abbreviation for 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 aluminum. High-performance BMX bikes use lightweight 4130 chromoly.

The introduction and widespread popularity of the cassette hub has ushered in the use of smaller gearing on BMX bikes. Most freestyle, street, and park BMX bikes, the wheels have 36 spokes. BMX Racing bike wheels vary in size, from 16" to 26", with 20" being the most popular.

Dirt jumping and freestyle bike wheel sizes include 16" and 18" for younger, smaller riders, 20" for most other riders, and a few companies including Haro and Sunday offer 24" freestyle bikes for taller riders who feel cramped on a standard 20" BMX bike.

BMX racing was a phenomenon by the mid-1970s. Children were racing standard road bikes off-road, around purpose-built tracks in California. George E. Esser founded the National Bicycle League as a non-profit bicycle motocross sanctioning organization in 1974. Some BMX riders go on to other cycling sports such as Australian Olympian Jared Graves, former "golden child" Eric Carter, and youth BMX racer Aaron Gwin. Conversely, Mountain Bike racers sometimes cross over to BMX Racing, such as 2008 Olympic Bronze Medallist Jill Kintner of the USA.

BMX bicycles are available in these models types:

1.      Dirt

2.      Flatland

3.      Freestyle

4.      Park

5.      Race

6.      Street

How To Pick The Right BMX Bike

Because people often throw around the "BMX" term generically, it's important to also understand that there are three different types of BMX bikes:

1.      The true BMX bike.

True BMX bikes started it all, back in the late sixties. BMX bikes are still designed for racing, although you don't have to race to enjoy the light weight, speed and dirt worthiness of these machines. They usually have 20-inch wheels, knobby tires, upright handlebars with crossbars, small saddles, long cranks and rear hand brakes; are generally made of chromoly steel, also come in different frame sizes.

2.      The freestyle bike.

It's a great bike for riding to school, the store and the pool. Super-sturdy construction is a higher priority than light weight. Freestyle bikes come with front and rear brakes.

3.      The dirt jumper bike.

They usually don't have front brakes and their brawny wheels normally feature 36 rugged 13-gauge spokes, rather than resorting to 48 spokes the way freestyle bikes do.

There are some important parts choices to make when purchasing a BMX bike:

1.  Wheels: It's crucial that the wheels meet your needs. Because accelerating out of starting gates is important in BMX, the wheels are much lighter than those found on freestyle or jump bikes. However, that 32-spoke light aluminum wheelset designed for BMX racing won't hold up to dirt jumping. So, freestyle bikes come almost exclusively with 48-spoke or mag wheels. Dirt jumper's wheels tend to be a bit more varied. Some dirt jumpers are equipped with just 36 super-meaty 13-gauge spokes. Others come with 48 spokes like freestyle bikes, depending on whether the bike is geared more for jumping or dirt riding.

2.  Tires: BMX tires straddle the line between pavement and dirt designs. Freestyle tires are designed for pavement and indoor surfaces. Dirt jumpers are usually designed for maximum traction.

3.  Handlebars: Bars found on 24-inch BMX and jumpers will be slightly shorter in rise than those found on 20-inch bikes.

4. Brakes: Freestyle bikes come with front and rear brakes. BMX and jump bikes usually sport only rear brakes. Brake type is also important. BMXers require pure stopping power so they prefer linear-pull brakes, which offers the ultimate grip. 

For excellent resources on bikes look at these.