27-04-2020, 01:17 PM
The problem with using a AFR meter to set the idle mixture relies on sufficient gas flow past the oxygen sensor. Unfortunately this doesn't happen and will give you false readings. Adjust the jet so that when you lift the piston with a small screwdriver the revs should increase slightly and then reduce as you further lift the piston. Sounds like you can set the idle mixture Ok when you say the engine starts to miss when you screw the jet nut all the way up.
I am running a 1" OM SU on a 3 bearing engine with a AH needle (probably need to check that). Running modern unleaded fuels will need some additional advance. A DK4 should give about 16 degrees advance so maybe start with about 5-10 degree initial to give a total of around 20+.
Don't know about a VS needle but can look it up if you like.
I am running a 1" OM SU on a 3 bearing engine with a AH needle (probably need to check that). Running modern unleaded fuels will need some additional advance. A DK4 should give about 16 degrees advance so maybe start with about 5-10 degree initial to give a total of around 20+.
Don't know about a VS needle but can look it up if you like.