We did this in the other direction against the advice of Willie who owns a small camping barn at the bottom fo the valley, similar weather too. Safe to say we were a bit scared of the drop down to the water from the track and did not ride much! We actually ended up getting a whole load of punctures on the top and were freezing cold but luckily found some guys out deer stalking who gave us a lift back down the valley in the back of their argo cat!