Dirt jumper 

1. A person who rides a medium sized fixed gear cycle that forms the look of a bmx bike with suspension, they are considered to be the most badass style of rider and they get the most pussy

2. A style of bicycle that is used to participate in dirt cycling and tricking

My boyfriend is a dirtjumper and I want his cock all the time.

I am trying to get my girlfriend to buy a dirt jumper but they are very expensive

Dirt jumper by AirMtb April 9, 2015

Dirthumper 

One who partakes in the humping of dirt.

Todd doesn't like chics. He's more of a DirtHumper.
Hey... so the guy likes to hump dirt. Whatever puts the eeze in your cheeze.

Dirthumper by Yankee Doodle April 14, 2004