Originally posted by Drivrfound
I've just intalled a new piston/sleeve in my MT-12 and I'm having trouble re-tuning. The main problem is I'm not very familiar with three needle carbs, I'm comfortable with the HS and LS needle, but the mid is screwing with me. Does anyone have the factory settings for this carb? or what are you running?
Thanks a lot guys,
P.S- I've just started to lean it out from breaking it in, and I find it's bogging at a little over 3/4 throttle.
HSN = 5 turns out, then start leaning 1/8th at a time if needed.
LSN = 3 turns out, then lean or open as needed to get at least 30 seconds idle without engine clogin to the point of dying, it should hesitate a little after 30 seconds but not die. To do this, let engine idle then press full throtle for a second or two to clean it out, then check the 30 seconds idle.
Mid Needle = flush with carb body with slot for screwdriver pointing the fuel inlet, then DON'T EVER TOUCH IT AGAIN.