Nice and sunny here in Scuthorpe so had a little ride to warm engine to do final setup. It starts easily and runs ok on higer revs but tickover is erratic, it seems to race for a few seconds when i close the throttle then after a while sometimes will settle down, if i reduce revs with the tickover screw it cuts out. So i did all the usual things, new plugs and points, timing set, checked for air leaks around rubbers etc then adjusted and ballenced carbs. There was an improvement but still not right, also carbs have been ultrasonicly cleaned and rebuilt,any ideas what else to check?