T.I. -- I'm Done Talking About Floyd Mayweather

T.I. says the beef between him and Floyd Mayweather is over -- and if you think he's going to spill any details about what went down between them ... think again.

The rapper was out in NYC on Monday with a few friends when our photog hit him with a barrage of questions about his recent fight with Floyd ... but T.I. insisted things were all good now.

As for why he wouldn't spill any details about the actual fight, T.I. explained, "He may be used to talking after his fights ... where I'm from, we don't talk after ours."