Mk3 commando carbs

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A question concerning mk1 concentrics fitted to 1977 mk3 commando.
Should screw in pilot jets be fitted ? (the ones that screw up into the body from the float chamber). I know all the tech docs suggest that they should not be there, and that the pilot jet is in the casing behind the adjusting screw, (which they are). But I seem to have a recollection that pilot jets (#25) were fitted. Any ideas
 
Should screw in pilot jets be fitted ? (the ones that screw up into the body from the float chamber).

No.

"Pilot Jets​


When first introduced, all carburetters were fitted with a detachable pilot jet screwed into a threaded hole in the bottom of the carburetter body. This arrangement is retained for 2 strokes, but from 1968, was replaced for 4 strokes by a bush pressed into the gallery behind the pilot air screw.
The detachable pilot jet caused problems with some 4 Stroke engines. The remoteness of the jet from the two pilot circuit outlet holes, caused starting and idling problems on bikes with lower manifold vacuums. This could cause stalling during deceleration, due to a weak mixture. The introduction of the pilot bush moved the pilot jet nearer to the outlet holes, overcoming this problem. The bush has a flow rate, equivalent to 20cc/min. Carburetters fitted with a bush, retain the threads originally used to fit the removable pilot jet."
 
No.

"Pilot Jets​


When first introduced, all carburetters were fitted with a detachable pilot jet screwed into a threaded hole in the bottom of the carburetter body. This arrangement is retained for 2 strokes, but from 1968, was replaced for 4 strokes by a bush pressed into the gallery behind the pilot air screw.
The detachable pilot jet caused problems with some 4 Stroke engines. The remoteness of the jet from the two pilot circuit outlet holes, caused starting and idling problems on bikes with lower manifold vacuums. This could cause stalling during deceleration, due to a weak mixture. The introduction of the pilot bush moved the pilot jet nearer to the outlet holes, overcoming this problem. The bush has a flow rate, equivalent to 20cc/min. Carburetters fitted with a bush, retain the threads originally used to fit the removable pilot jet."
Excellent, thank you
 
A question concerning mk1 concentrics fitted to 1977 mk3 commando.
Should screw in pilot jets be fitted ? (the ones that screw up into the body from the float chamber). I know all the tech docs suggest that they should not be there, and that the pilot jet is in the casing behind the adjusting screw, (which they are). But I seem to have a recollection that pilot jets (#25) were fitted. Any ideas
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