rikkisbears,
On Tyros the midi channels used by styles are all transmittable externally - for example if they weren't it would be difficult to make midi recordings on external sequencers. (I was able to record my aged PSR 7000 this way too).
On Tyros Channel10 (and sometimes 9 ) is used for percussion. The desired transmit (and receive) channels can be selected, various properties set and stored as templates.

John