It might not even be the English saddle that's causing the horse to act differently. Like the OP said other people have tried him English so I would assume that would mean different English saddles. It might be the rider or riders. 90% of horse related issues are caused by the rider.
I'm not saying the OP or anyone else is a bad rider but your legs are in a different position in an English saddle. Perhaps the horse is uncomfortable with where your legs are. Or maybe it is rider related.
Either way jump western at your own risk. I wouldn't do it, that just screams internal bleeding. Posted via Mobile Device