Make sure to disable the option that dismounts you if you hold tap the right side. Trikes have a charge action that interferes with that. To charge, mount one, double tap/double swipe up and then hold, on the right side of the screen and it will charge. I also recommend having autorun always on, to prevent some tames not registering sprinting and instead running, like Iguanodon(even if you do it correctly, double tapping and then holding).