WARNING: THIS VIDEO IS TERRIFYING!!!
A motorcycle racing champ crashed his bike on a hairpin turn during a race in Spain on Sunday ... and the guy is lucky to have only escaped with a broken arm.
Here's the deal ... Marc Marquez -- a superstar champion in the MotoGP world -- was flying down the track during the Spanish Grand Prix when disaster struck near the end of the race.
The 27-year-old went into a turn ... but his bike wobbled, hit the pavement, and launched Marquez FEET into the air.