Brazilian Legend Royce Gracie -- Hey, Ryan Lochte ... COME CLEAN ALREADY!

Brazilian MMA legend Royce Gracie has a message to Ryan Lochte -- cut the crap and tell the TRUTH already!

We spoke with Gracie moments ago about the Lochte situation in his home country -- and Gracie told us he's sick and tired of the lies.

"You are a professional athlete. The young generation is looking up to you ... come clean."

Gracie believes the root of the problem is alcohol -- with Brazilian officials saying Lochte and the other 3 swimmers were hammered when they vandalized a gas station bathroom in Rio.

"He needs to clean up his act and stop drinking," Gracie says ... "People will respect him more."

"As an athlete I am on a different level. I don’t drink, never smoked. He should know that and he forgets what the life of an athlete is."