drewnabobber

I had a Rev 4T 250. Great bike, very easy to ride, but lots of little issues with those older bikes - hard to find parts these days (especially the shock) unless you know the right people. I sold it and got an Evo 125 and don't regret it for one second, the little beta is so much more fun to ride. I would avoid the 4T just for the maintenance issue alone, never mind that the 2T is lighter and easier to start. 125 still has enough power to toss you off if you mess up.

Beta is most common around here, but Scorpa and TRS have good support as well. If you talk to Bob at Mountain Motorcycles he might be able to help you with a test ride, especially if you're buying a bike from him - he carries Beta and TRS. I know most guys are happy to let someone have a quick ride on a bike, so probably just try to make some friends and I'm sure you'll be offered some rides. If you buy used you won't be taking a risk as if you don't like the bike it's easy to shift onwards. Honestly I'd buy the one that you like the looks of best as they are all great bikes these days. Not sure about White Rock. Most riding locations are northwards in the mountains. Squamish, Iron Mountain and Mcnutt (Mcnutt is really for enduros though) are some places to ride outside of Ioco.

Trick in the mud is to keep the caliper clean. They are only a single seal so get fouled and stick very quickly. Strip it down and clean everything fairly regularly.

Get in touch with the local trials clubs and start asking around if anyone might have a bike for sale. Seems that the smaller bikes usually go between friends or club members and are never advertised.

I just started riding trials, similar to you I came from road racing and supermoto. I ride a 125 beta and have ridden a friend's 300 a couple of times. You'll be fine on a 300, but there is a lot more motor there. But I really enjoy riding the 125 and I've never felt like the motor is holding me back. Rather the opposite, I really have to focus on exploiting the clutch and flywheel to move the bike around. I've always enjoyed flogging little bikes, and this is no different. Horses for courses as the big bike was fun too, but I hardly had to move the throttle. Some people prefer that. Probably more important to get a bike in good shape and start riding than worry too much about displacement.