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Acceleration Misfire

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K2-K6:
I do think its worthy of debate here ... thank you to the contributing debaters in following this topic through.

If a statement of this type can't be usefully examined, cross checked and verified ... then really its probably myth in quality.

Things like this must be able to withstand reasonable scrutiny to hold a validity in making adjustments to these carburettor and engines.

There is ... in official workshop manual of 750 ... an engineering drawing, in section vertically through the carburettor and with noted key parts.
Subsection of that drawing is an expanded view of the idle circuit junction/interface showing decent enough detail.

It's also split in vertical plane (important here) and not derived into plan view, usually signified in technical drawing by 45 degree extraction notification to make clear that has been accepted. It's important here as that expansion diagram could be inadvertently "read" as an airscrew illustration if it was indeed plan view. Its not.

What that shows is a side view, sectioned vertically of the idle jet, installation and emulsifier tube in situ. This has an air passage disecting it around the emulsion tube height. There's no modulation drawn for adjustment of that fuel supply route, at all. It's just plain through from idle fuel jet orifice, up the tube and through the emulsifier toward venturi.

If that drawing was mistaken for an adjustable compartment (the sectioned jet lookin like a needle type adjustment screw, because it's section illustration has similar form) then someone could make the incorrect interpretation, based on that detail, that it is a different component.

I'd be honestly surprised if it could be shown that this design could work in tbe opposite of that which we understand it.

TIM1954:
Generally speaking the Coils tend to fail as the bike gets hotter. Worth checking them out.

Seabeowner:
Always fascinated me this discussion on mixture. When on tickover or very low revs how much of the air goes past the the carb sliders and how much goes via the air mixture screw (not much)? Where does the air that passes the screw feed in? Still have an open mind.

Bryanj:
There is a small brass orifice below the slide on filter side of carb

McCabe-Thiele (Ted):
Here is an observation I've made on my 500.
When the engine is started from cold (Summer time) I do not like to use the choke so it's soon off. I made the error a couple of days ago of screwing down the main throttle bracket screw 1/4 turn to make it idle when only part warm. As I rode off it started popping and banging like crazy. I returned home thinking something was very wrong  - by this time it was well up to normal running temperature so the idle was 2k plus hanging throttle. Returned the throttle stop  screw to idle again at 1100-1200 rpm as engine was warm. Blipping the throttle now no popping or banging, no hanging idle. Went back out for ride all was good. Using the choke plus it's fast idle from cold is different - no popping or banging. The only difference I could work out was the hanging throttle here was caused by the sliders being prevented from closing to the correct position.

This has led me to believe that hanging throttle issues are as a consequence of the sliders not being sufficient closed in the shut throttle position. If the sliders are in the sufficiently closed position any idle speed adjustment should be made via the air screw only.

I think the trick might be knowing what the sweet spot is for "sliders  are sufficiently closed".  Open for debate

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