One of the last runs i did on my Ariel on the way home the engine was labouring so pulled up and it was covered in oil the engine had wet sumped and blown all the oil out of the breather and mag drive so Maz had to come out and tow me home
The plunger pump had got a bit of muck under the ball valves that was it ..cleaned it and re-seated the valves and clean oil but off putting it had never happened before ..prob could do with a new pump..