Considering buying a 4t, more just for the hell of it rather than actually to do trials on but was wondering other than heavier weight what else do I need to know about riding them ???

 Usually just the grin on your face as they are great fun just to ride.

Found I used the clutch on decelerating to reduce unwanted engine braking. I never got the hang of riding one uphill on compact clay/mud as I do with a 2stroke. 

Considering the beta 4t. I had a scorpa 163 a few years back, brilliant bike, should never have sold it but couldn't ride a trial for toffee on it, most would say I still can't no matter what I'm on to be honest.