Well she finally fired up after 8 months of rebuilding and 50 kicks or so while I tried to figure out which jets to use and idle/air screw settings. However, she don't exactly run that well and I could use some input... First off, the setup: 73 750 running single 34mm Mk2 just cleaned and rebuilt with all new jets and needle (270 main, 106 needle, and 30 idle), big bore 1.5" exhaust system, Pazon statically timed to 31 degrees, new battery, new plugs and leads, Lucas 12V coils (i.e. not new).
It still takes a couple kicks and screwing with the carb screws and throttle before it stays running, and even then it won't idle below 1500 or 2000 without conking out at some point. When it's warm it's marginally easier to start but idle is still inconsistent.
All signs point to lean running: popping even at idle, stumbling off idle when running, lurching and general unsteadiness at low throttle openings with popping. A quick goose of the throttle at idle is guaranteed to backfire if not completely stall it out. Plus my new pipes are already deep yellow. Grrr.... This is all after swapping my idle jet up to 30 from 20, and the biggest idle they make as far as i know is 35. Air screw position seems to make little difference with the 30, and actually when the 20 was in it wouldn't even start unless the screw was fully closed.
But wait - there's more! After all this, even after running for a couple minutes my plugs are completely black, though at least they're dry.
My personal theory is that the Pazon needs 6V coils. They recommend two 6's or a single 12, but say that dual 12's will work on "low" compression engines. Resistance readings across both coils fall within standard specs.
I thought, not being a Combat, the compression on mine was low, but maybe it's borderline and it really needs two 6's instead? Or am I way off thinking it's the coils?
It still takes a couple kicks and screwing with the carb screws and throttle before it stays running, and even then it won't idle below 1500 or 2000 without conking out at some point. When it's warm it's marginally easier to start but idle is still inconsistent.
All signs point to lean running: popping even at idle, stumbling off idle when running, lurching and general unsteadiness at low throttle openings with popping. A quick goose of the throttle at idle is guaranteed to backfire if not completely stall it out. Plus my new pipes are already deep yellow. Grrr.... This is all after swapping my idle jet up to 30 from 20, and the biggest idle they make as far as i know is 35. Air screw position seems to make little difference with the 30, and actually when the 20 was in it wouldn't even start unless the screw was fully closed.
But wait - there's more! After all this, even after running for a couple minutes my plugs are completely black, though at least they're dry.
My personal theory is that the Pazon needs 6V coils. They recommend two 6's or a single 12, but say that dual 12's will work on "low" compression engines. Resistance readings across both coils fall within standard specs.
I thought, not being a Combat, the compression on mine was low, but maybe it's borderline and it really needs two 6's instead? Or am I way off thinking it's the coils?