I have found that the Triceratops/Trike prefers the tintoberries, my strategy for taming lvl 10< Trikes on a new charachter i usually grab around 40-100 tintoberries and 3 or 5 narcotics/10-25 narcoberries and i use the starve method for around 4 minutes before using a narcotic and putting the berries in!
The trikes are amazing for gathering a huge amount of narcoberries, i ride my Trike to the hills and keep hitting the bushes and then I access the Trikes inventory and grab what i want to keep and then press drop all items for the Trike.
They are easy first get slow level if you are start game. Preferably a lvl1 to a lvl 10. Then knock it out with a slingshot or tranqs. I run in circles and knock it out. After that let starve for 3-5 minutes then feed green kibble ,crops , or mejos. After that give either narco berries or narcotics. Then you got a trike.