ok, idle circut/idle jet, first 1/4 and take off.
needle, control of flow thru midrange, step down to lean, step up to fat.
main jet, change for WOT(why am i fine thru everything, including WOT up hills or in low rpms, but then FAAAT keeping my speed down)
so then they also sell many diffusers with different diameters, which part of the range do those control/effect? all of it? how? a smaller one is less fuel/more air mix???
or what....
anyone.. diffuser does who what?
david do some footwork urself for once, this took me, 3 min on google:
http://www.thisoldtractor.com/gtbender/mg_manuals/dellorto_manual.pdf
http://www.thisoldtractor.com/gtbender/mg_manuals/dellorto_manual_a_guide_1.1.pdf
the source:
peace
argh watever i can't back track to the source but u got enough right there
i read all the dellorto stuff i could find and it didnt say shit about what range the diffuser controls.
i am not good at the internet
sick tho
thanks
Two references (or links) were provided.
Page 2 of the second reference says:
In the C high-speed control period (which is between 1/4 and 3/4 throttle opening) mixture delivery from the idle circuit and from the progression hole is replaced by mixture from the main circuit and selection of both the atomiser and the tapered needle should be made.
BTW, atomiser = diffuser = emulsion tube.
Quote:needle, control of flow thru midrange
First off this statement is wrong. Your seeing it as your rev range. Thats wrong. When it says idle thru 1/4 and mid range. Its not talking about your rpm. Its talking about throttle opening. The idle circuit/jet is controlling idle thru 1/4 throttle opening. The needle controls with some overlap 1/4 to almost full throttle, throttle opening. Then the main jet controls Wide open throttle.
Are you getting it. Adjust your needle if your rich at your mid throttle opening.
As far as the diffuser. I don't own a dellorto. But. Lets take the standard Puch Bing and use it as an example. A 15mm bing comes with a 2.17 diffuser. This is the inside diameter. Using a 2.20 will cause your needle to allow more fuel across the board. Which will effect your needle settings. The Puch bing does not have an idle jet so to speak. This is it. Larger equals richer, smaller equals leaner.
So say I have a Puch polini with a bing. I find that I really can't adjust the needle to a position I like. And or its lean at idle. I would increase the size of the diffuser to richen my idle. And since it richens all my needle settings also, I have to readjust my needle to compensate for the richness at part throttle.
Basically your just changing the relation of the orifice to your needle.
Want to post in this forum? We'd love to have you join the discussion, but first: