Thanks Kevski for the tip, I'd like to try it but I really think I've got a duff set of fuel valves from Keyster.
I'm going to buy 4 new valves from DS, they are 14 quid each
and I don't know the make of them either, I do not they are not genuine though. DS sells the Keyster kits for 19 pounds each but I've been down that road before so not buying another kit only to suffer the same problems
I never had this hassle with the dellorto's on both the Morini and the Jota and the Amal's on the Triton were a piece of cake in comparison
I should have bought a rough bike but a runner, at least I could have heard it running and would have known the potential problems, the carbs on this one were in pieces in a box.