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Cleaned carbs now have a hanging rpm issue
- Thread starter dman1049
- Start date
It sounds like the carbs or an air leak; if it was ignition it wouldnt idle right. Ignition should affect the engine at all stages I believe, even at idle.
If there are no signs of leaks and it seems to idle fine check the main jets, emulsion tube, needle, needle height, and measure the float height.
The carbs sort of transition from pilot jet control, to needle control, to straight up main jets with some overlap. So, at 1/4 to 3/4 throttle or so you're looking more at main jet circuit and slide needle.
If there are no signs of leaks and it seems to idle fine check the main jets, emulsion tube, needle, needle height, and measure the float height.
The carbs sort of transition from pilot jet control, to needle control, to straight up main jets with some overlap. So, at 1/4 to 3/4 throttle or so you're looking more at main jet circuit and slide needle.
On my 78 unscrewing the idle screws 8+ turns is the only thing that would get it t start with my emgo shorty mufflers; it would not start on less than, say, 4 turns out. Loosening must be making it richer.
I just thought of something though. Dman, the title suggests you didnt have any problems before cleaning the carbs, but now you do after you cleaned them? You probably did not tighten a connection well enough on the air intake side or carb boots. Maybe the gaskets and seals were fine before, but since they sat for a long time and you broke them free they are no longer sealing well.
I just thought of something though. Dman, the title suggests you didnt have any problems before cleaning the carbs, but now you do after you cleaned them? You probably did not tighten a connection well enough on the air intake side or carb boots. Maybe the gaskets and seals were fine before, but since they sat for a long time and you broke them free they are no longer sealing well.
On my '79 (original carbs) it's screws out to make richer. I'm at about 3.5 out.
it wouldn't start without starting fluid or gas directly in the carb and the bike would only run briefly before cleaning them. the jets were all completely clogged. the diaphragms wouldn't open either. it all was cleaned and soaked. ill check for air leaks better.
marmite69
XS400 Member
what was it dman in the end just for reference
