Bmx Dirt
Dirt jumping is where BMX began.
Dirt jumping is kind of split into two different forms: 'trail riding' and 'dirt jumping'.
'Trails' is the word used to describe a collection of dirt jumps.
Trail riders generally prefer to spend their time in the woods, building more and more jumps that link all over the place for them to flow through.
'Dirt Jumping' is basically what you see at the X-Games: where there are two or more HUGE jumps and riders try and do as many tricks over them as possible.
Dirt bikes are generally heavier than a race bike, but lighter than a street bike (although they can be used for both if you're smooth enough).
A dirt bike will usually have no pegs and may or may not have a gyro.
Dirt riders also tend to use wheels with 36 spokes which are lighter than street wheels and they use race-style two piece-bars.
Some great dirt jumpers include: Stephen Murray (UK), Kye Forte (UK), Neil Wood, Mikey Aitken, Taj Mihelich, Migalla, Brian Foster (all USA).
The basic idea in dirt jumping is to get up as much speed as you can then hit a ramp built up out of dirt and pull off a trick which is graded by difficulty, originality, and smoothness of the landing - although the grading also depends on the judges!