I have a 52 A10 that has had a restro and only done 300 miles. Everything has been rebuilt in the engine, mag overhauled, new everything but has ben fitted with a concentric carby. Problem is it starts easy, idles sweet, accelerates well everything nice. Once it gets hot when you come back through the gears at an intersection everything is fine until you nearly stop and then it cuts out. If you are quick enough a little throttle will keep it running. It starts again easy as but will cut out if you let it drop back to idle. A couple of revs for a second or two and it will idle. Plugs are burning nice, valves at 10 thou, as far as I know timing is right, carby has a 3 cut away,needle on third notch, tried second no different. Got me buggered