Cool, cleaned up the piston from the old carb and swapped into the current carb and its like night and day, feels so much more grunty and revs out nicely.
can actually see on the old piston where it has been sticking, will probably strip the carb down and give it a decent clean over the weekend.
Only issue that it has now is if you rev it and then let off the accelerator it drops smoothly to 2000 rpm then hesitates there for a second before dropping to idle, not a big deal though. can drive it tomorrow.
Also, the stupid screws that hold the top cover on are made of the softest metal, had to take the vice grips to a couple