1969 Commando revitalization.

Swarf is chips left over from machining operations, that includes the pilot circuit.

The pilot screw setting is a guide only.
The air circuit can get easily clogged up, as already said, but the final setting must be done on a warmed up motor to obtain the best idle. This can vary between carbs on the same bike, so fine tuning of both sides is key, and in conjunction with the idle screws.
they can be as low as half a turn from closed.

Jackman said:

What’s a swarf?

Carbs are spotless but I didn’t take the bowls off.

Click to expand...

Take the bowls off.
Swarf is drill chips, etc.
Also check that everything is snug. My jet holders were loose from new.