Casper Smart SLOW YOUR ROLL!! Gets Probation for Drag Racing

1/3/2012 4:20 PM PST

Casper Smart -- J.Lo's Boyfriend Gets Probation for Drag Racing Arrest

Jennifer Lopez
might want to think twice about handing Casper Smart the keys to her Bentley ... 'cause her BF just pleaded no contest in a drag racing case.

Casper's high speed bust came back in April 2010 -- long before his J.Lo days -- and today an LA County Superior Court judge hit him with 12 months probation and a $500 fine.

Casper wasn't required to be in court ... his attorney entered the plea. We're guessing speed racer had better people things to do.