the rapper filmed himself doing the deed MORE than once in recent years ... and TWO tapes are currently being shopped to the highest bidder. 

Kanye's sex tape featuring a young Kim look-alike in a hotel room is definitely making the rounds -- And there's a second tape and the 2 are nearly identical. 

Both tapes are impressively long -- the first is roughly twenty minutes ... and the second is more than FORTY. And we're talking constant action. Seriously, the guy takes no breaks. It's incredible. Almost Sting-like. 

Tthe tapes were both shot several years ago with exes.

The tapes are currently being shopped to media outlets by a third party. 

Sources close to Kanye, has no idea how the videos were lifted from his computer -- but if anyone releases the footage ... Kanye plans to go after the culprits with a legal vengeance.