Playing the bell off the time becomes natural with practice.
You may learn it faster by practicing first hitting the bell at exactly the same time you're hitting the skin, then adding one stroke on the bell just before the first stroke on the skin.
It becomes easier when you're already acquainted with off the beat accompaniments on djembe.
Also it's a cognitive thing : listen to lots and lots of dunumbas so that your brain gets used to those off the beat strokes, it will make things way way easier. People often struggle with it, because they don't realize the problem is cognitive, they think it's physiological (moving the arm at the right time), so they assume it's only about hitting the bell at the right time (it never works), whereas it's a whole new perception of time and rhythm that is involved (ie a rhythm that is off the beat).
But if you can't play the kenkeni bell off the time, yet I do not advise playing the bell with one stroke on the time. It kills the feeling of the dunumba you're playing.
You're better off not playing the bell on the kenkeni, the bells on the sangban and the dunumba will make a great melody.
Listen to lots of dunumbas, practice and don't give up, everybody can get it.
Kawa
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