The following is from my files...
"Idle by Carston"
Carston used to be active online and his experience and know how about these Bullets was extensive. A couple of years ago he started on an Enfield web page but it vanished... don't know what happened to him.
- Mike
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Idle...
The idle mixture is adjusted by the pilot air screw. Clockwise rotation of the pilot air screw richens the mixture. The idling speed (rpm) of the engine is adjusted by changing the closed height of the throttle slide, using the idle speed screw. The pilot jet size controls fuel flow. Jets are stamped with a number indicating the fuel flow in a given time.
A good start is to close the pilot-air srew carefully and to re-open it 11/2–2 turns again. Never tighten the pilot-air screw, this will demage the carb. The 11/2 turns correspond to one pilot jet size. If you have to turn more, use the next larger/smaller pilot jet instead. Set the idle rpm to a slightly higher speed than desired later. Open the pilot air screw until rpm drop and close it until rpm drop again. Adjust to the middle of these two settings. If the engine does not respond well to throttle opening (hesitates, stutters, stalls), you need a larger pilot jet. If the spark plug fouls (decreasing rpm until the engine stalls), try a smaler pilot jet. Finally, adjust idle rpm using the idle speed screw.