Plenty around
Try TRF
Head towards Llangollen, when you get near Pontcyllit viaduct head up and over the top, Splashy Lane, Alt Y Bady, Bwlch-y-groes (small bike only), Wayfarer, Bomber Lane (near Barmouth) all doable with big bikes, done them all on my ATs. There's aso the Corwen Car Wash but steer clear the next few days as you'll be beyond your headlamps due to the rain coming in
Mike's your man, beddowsm, on the forums and some info on ABR