Yes, it's annoying that the wretched fault is so persistent, after a couple of months' peace it reocurred again yesterday. I got some new float valves a couple of years ago, but with little improvement- well, fair enough, I suppose, if the fault really is due to crap in the fuel, but I've flushed the tank out. And every time it happens I take the bowl off the carb and remove the float hinge pin, the float valve then drops out and I give the system a quick flushing by briefly opening the fuel cock. I catch the fuel coming out in the float bowl so I can see the crap, but recently there just isn't any to be seen. I do this at the side of the road and it only takes a few minutes, I've done it a few times by now. Also, each time it happens I first of all give the float bowl a tap with a spanner or something just in case its a case of the float or the valve sticking, but that's never worked yet. So I'm getting bloody fed up with it by now. I'm wondering if it would do any good to change the valve seat- any suggestions, anybody? No, I haven't tried filters, they might be the answer, I'd be glad if you could keep me posted, Hans.