How do you subdevide polyryhtms over two or more beats?

Question:

How do you subdevide polyryhtms over two or more beats?

Ok I get the idea of tuplets such as triplets or sextuplets, but say I'm playing some jazz or some Zappa stuff. I find it hard to work out how I'm meant to play a complex polyrhythm, for example 7:3 crotchet over 16ths. If I can listen to the recording I can work out how I'm meant to play the rhythm but just reading a sheet is incredible hard for me to do. Any tips on how you can accurately work out such polyrhythms

Best Answer - Chosen by Asker: I've had trouble with this too, especially the weirder ones (5:4). The problem is that no one can really tell you how to do it, it is mostly trial and error. I'm a guitar player and although you wouldn't think our kind would be delving into poly rhythms that much, I felt the need to do so upon being accepted to a school for Jazz. How I worked it all out was by drilling them repeatedly and finding commonality in the overall "sound" of the subdivision. For example, if you're dealing with a five or seven subdivision feel, there is going to be some kind of displacement. A good musical example of 5:4 would be Penguin in Bondage by Zappa. The whole band at one point launches into quintuplets and for me, it totally cleared up any confusion on the subject. But dude, the key is repetition. Listen to different examples of subdivisions and, as I said earlier, drill them. Your best aid for nailing these things is something audible; like a recording.