These guys are op I mean I just killed 10 carnos with a trike if your trike is higher or equal in level to a carno or therizino it can easily fight them because of it's knock back attack just pump health, meele damage and stamina. They are great for collecting thatch and berries.
Trikes are a great harvesting mount for berries and thatch. They also have good attacks (which do knockback to smaller dinos.) My favorite attack is the charge attack. I use it to raid wood/thatch bases. Overall great mount!
I can not stress enough to my friends how useful the trike is. Early game it makes a great pack animal. Late game in groups of three or four it can be used as a decent battle mount. Taming a trike early on can be a great way to start a large base and keep you well fed with berries.