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Amal mk2 single carb jets

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I have just purchased a 750 commando with a single my 2 concentric carb,it's is sotting the plugs up,can anyone help me with what size jets etc should be fitted thanks,Andy 

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First check that you are operating the enricher correctly ie lever up is off and is it functioning correctly , the small black seal can come adrift and disappear. Check the air screw is between 1.5 to 2.5 turns out.
From memory the jetting is, Pilot jet 15,  Needle jet 107, main jet 160 rings a bell. Slide I used was a 3 but others use 3.5. The standard alloy slide will hang up, you'll need a stronger spring or a chromed brass slide that's expensive so make sure you know the size you require before going down that path.

Thanks for your reply,I will check all of the jet numbers and the choke tomorrow and let you know what I find,also what notch should the needle be in,thanks Andy

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Also be aware that the carb settings are the same regardless of whether you have one or two carburettors.  So the book figures for the original twin carb setup should still apply.

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Chances are the needle jet is worn, so a new needle and needle jet is a good starting point. Bear in mind there are several jets at difference openings, which one is causing the sooting (won't be the main jet which doesn't wear)

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Hi Andy, I had trouble with the lever choke system on the Mk2 Amals not seating properly after a few months use and causing rich running, I changed them for cable pull type and had no further problems.

 



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