276 GG pilot circuit

[Clive54bsa]

Does anyone out there happen to know the orifice size of the pilot fuel circuit, my "54 is lean just off idle and spits back through the carb when I "blip" the throttle at a stop, I've richend it everywhere else, #3 slide, raised the needle, etc. Bike runs great, just that "off-idle" spot.
I'm in California, so there's the crappy petrol issue, 91 octane is the highest pump petrol.
Clive

[chaterlea25]

Hi Clive,
The pilot jet size is stamped on the top of the jet block
Attached is a comparison chart to figure out the size,and one of the internal passages
Before you attack anything make sure the fuel height is correct
Usually theres a plug on the float chamber banjo where you can jam in a piece of small plastic tube
Bring the tube up the side of the carb by the pilot screw, fuel level should be up to the bottom of the air screw hole

John

[Clive54bsa]

Thanks for that John, this site is a wealth of information.
My jet block is stamped with what looks like either a 5 or 51.
The idle orifice seems to be somewhere between .018 and .025"
I don't have any way to accurately measure it. My plain guitar strings only go up to 18 thou.