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Is this right?

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Oddjob:
In richer, out leaner. Never heard anything different from Honda on any course, saying that it may change with CV carbs for instance. They tend to have the screws in different places on the carb body so may react differently.

K2-K6:
Also same for me on these carbs fitted to sohc 4 engines, inwards makes it richer, out makes it leaner.

Didn't realise the author initially, thought before it's a strange view of it though.

There's a mix of metering method and setting the mixture kind of overlaying within a "conversation" there, which makes it seem convoluted. Wonder if anyone has asked or had communication as to why he thinks it's that way as written there.

Just checked manual for PD type and next generation CV carbs (early 80s) with neither stating which way turning the screw affects the mixture. They, both type,  have the adjustment screw on underside of the venturi engine side of carb, that's in comparison to the older slide type we are talking about here.

Herr Supersport:
It's not my plan to bash somebody - on the contrary. But as a longtime-lurcher I probably can point to a link explaining "why he thinks it's that way as written there". Second post.

http://forums.sohc4.net/index.php/topic,182280.0.html

Wasn't that easy to understand for me, german-speaking guy. Even if I live in Bernoulli's town ;).

JamesH:

--- Quote from: Oddjob on June 13, 2023, 12:43:44 PM ---In richer, out leaner. Never heard anything different from Honda on any course, saying that it may change with CV carbs for instance. They tend to have the screws in different places on the carb body so may react differently.

--- End quote ---
What Ken said...

K2-K6:

--- Quote from: Herr Supersport on June 13, 2023, 04:15:30 PM ---It's not my plan to bash somebody - on the contrary. But as a longtime-lurcher I probably can point to a link explaining "why he thinks it's that way as written there". Second post.

http://forums.sohc4.net/index.php/topic,182280.0.html

Wasn't that easy to understand for me, german-speaking guy. Even if I live in Bernoulli's town ;).

--- End quote ---

Bernoulli...for anyone with a technical interest in F1 currently, the application of his work by RB technical team is quite impressive  :)

Thankyou for the link, I've read through there before and can understand why,  when translated or interpreted by a different language speaker, it seems confusing. It certainly wanders around through some very tenuous relationships used to demonstrate principles.

Some that caused me to question it when reading to myself, reference to Honda 250/6 1960s race engine missed the point of low rpm running completely, from my understanding of that bike.
I think I recall correctly that it had no idle circuit in carburation at all, revving it while stationary the only way to keep it running. It is a very radical engine though with approaching 300bhp per litre and still would be if produced now.
Principal among the need to rev it though is a crankshaft that has different sized main and big end bearings on outside cylinders, getting larger as more torque was added with each successive cylinder to take drive out from crank centre. Apparently so marginal in strength that you can twist the built crank assembly out of line by hand ! Riders had to keep above 14,000rpm in driving it to avoid doing the same to the crank. There was simply no need for any idle provision in carburation, it's not a good example to reference in my view.
Demonstrated by Steve Plater in recent times at IOM TT circuit, he stalled it twice from not concentrating on keeping it revving when slowing down and had to bump start it on the run, a very highly strung dramatic engine.

A few post down that thread,  there's reference to positive fuel pressure on pumped system such as Honda gold wing (lift pump from tank) that seems to infere that this would give PRESSURE at the jets ? When in reality the float chamber is always at atmospheric on gravity or pump fed carburation system.

It just seems odd there's so many points that don't add up.

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