K2 -On it's way to becoming a major player with a single, compelling concept: action sports share many similarities, and a brand name in one gains an advantage in another. That's why K2 makes snowboards, in-line skates, bikes, and surfboards. They teamed with Shimano to invent the first click-in snowboard binding. They sponsor the gnarliest event in all sports, the Big Wave Surf Challenge. These guys will rule the world because they understand two important things: what these activities have in common - and what they don't.

K9 - Bad news on the road if a K9 is chasing you. Synonyms: Dog

Kack - an injury to the shin received while doing trials, a kack can be the result of any injury receive during technical riding.

Kick-Out - a bunny hop in which the rider pushes the back tire to one side.

Kids -Where are they? Maybe our sport requires too many bucks and too much suffering to appeal so much to the young. They definitely seem to be choosing snowboarding, skateboarding, and BMX over off-road cycling. Anyone care to answer why?

Knickers - These either look ridiculous or really cool. Once upon a time, wearing knickers was considered a fashion must for autumn riding. Kind of made invalid by the advent of rideable baggy shorts (see "Nema.") Besides, chaps are sexier. And off-road leiderhosen...ohh, baby! Now that's foxy.

Knievel, Evel -Who could argue: without Evel, mountain biking would never have been possible.