Chaz Bono -- Rhythmically Challenged

Chaz Bono will make a splash on "Dancing with the Stars," but people who have known her and him well tell TMZ ... it may be more like a belly flop.

Our sources say ... as a woman Chaz had NO rhythm, and there's no evidence any of Chaz' recent changes improved the situation.

The people we spoke with were very surprised Chaz agreed to the DWTS gig, but say it's more about making a statement than the dancing itself.

On the bright side, our DWTS spies tell us Chaz is well-liked among the professional dancers and contestants -- "a very cool dude," one source says.