Ride your dirt bike on unusually challenging obstacle courses and try to complete all the levels, in this ad...  (更多)renaline pumping action game. In this extreme dirt biking game you have to ride your dirt bike through various challenging obstacle courses and try to complete all of the levels successfully. Be warned though, this game is highly addictive!Be careful as you make your way and remember, that you must utilize all your skills to get past all those obstacles without getting injured. You can retry a course any number of times, if you fail. Try to finish every level in the least time possible to gain higher points. Go ahead take the challenge...  (减少)