Hi guys,
When I started the saw the first time after the muffler mod. One thing that I noticed was how it idled faster. Before the mod I had it set to 2800 and after the mod it was around 3400.
It was really interesting to see how opening the exhaust increased the idle. Is it because it would be somehow running slightly leaner? Or is it because air can travel less restricted so for the same butterfly position air passes more freely past it?
the increase in idle is a great indication that the mod helped it breath better either way!
Am I right in thinking that it’s not idling higher because it’s running leaner because, yes more air passes through, but a proportionate increase in fuel amount would flow through too?
I remember reading this, but I can’t remember where...
EDIT: I may have answered my own question now that I look back to what I did earlier. I remember that I opened the L screw a little to fatten it up which would decrease idle) for fear that it could have been lean, and that resulted I a slight (rich?) bog / burble / hesitation off idle on acceleration. Therefore I returned it to the original setting (screwed the L back in / slightly leaner) it it ran cleanly and then just lowered the idle screw instead. This makes me think, it wasn’t running faster at idle because it was lean, it was running at idle faster because after the mod more air can pass through the same Butterfly opening?
Be gentle, I’m still very new at this ha.
I’d love to try and understand this, if you could shed some light on the subject and what’s happening that would be great!
When I started the saw the first time after the muffler mod. One thing that I noticed was how it idled faster. Before the mod I had it set to 2800 and after the mod it was around 3400.
It was really interesting to see how opening the exhaust increased the idle. Is it because it would be somehow running slightly leaner? Or is it because air can travel less restricted so for the same butterfly position air passes more freely past it?
the increase in idle is a great indication that the mod helped it breath better either way!
Am I right in thinking that it’s not idling higher because it’s running leaner because, yes more air passes through, but a proportionate increase in fuel amount would flow through too?
I remember reading this, but I can’t remember where...
EDIT: I may have answered my own question now that I look back to what I did earlier. I remember that I opened the L screw a little to fatten it up which would decrease idle) for fear that it could have been lean, and that resulted I a slight (rich?) bog / burble / hesitation off idle on acceleration. Therefore I returned it to the original setting (screwed the L back in / slightly leaner) it it ran cleanly and then just lowered the idle screw instead. This makes me think, it wasn’t running faster at idle because it was lean, it was running at idle faster because after the mod more air can pass through the same Butterfly opening?
Be gentle, I’m still very new at this ha.
I’d love to try and understand this, if you could shed some light on the subject and what’s happening that would be great!
