Mainjet and NeedlePosition-Do these affect idle?

[blasternoob]

Just like the title says, will either of these affect idling or cranking? I don't know much of anything about a carbeurator, but I've read where these 2 affect half to W.O.T.

 

[BLASTER POWER]

yea tat could be the cause here is sum diagram of the carb to help ya think i got it off de forum ??
hope it helps!!!

 

[impulse86]

f I remember correctly the pilot jet controls idle and yes needle postion does as well the main jet controls from 50% to 100% throtle range

 

[blaster biotch]

needle clip effects idle as well as wot. it meters the are passing through at any given time

 

[wrench man]

NO, not really, they do to a minuscule amount
Like when I was tuning my carb, every one said "when the clip gets to the end of the needle change the pilot jet" , BULL sh*t!!!!!!!, you NEED to change the NEEDLE JET!

this is what MIKUNI says.

 

[quam]

when the engine is idling, the condition of the carburator is as follows: the slide/butterfly has the air almost completely blocked off (unless the carb utilizes an air jet, then it IS completely blocked off) through the venturi, the pilot jet is issuing fuel to the small thread of air passing through the remaining gap in the slide/butterfly/air jet, in the stock blaster's carb the pilot jet issues a constant amount of fuel and can only be adjusted by changing the size of the jet (this is not the case for all carb types) and the pilot mixture is adjust via the air screw which moderates the flow of air through the pilot circuit, the main jet is mostly blocked off by the needle. if the carb is set w/ a VERY low idle speed then the main jet could very well be completely blocked off by the needle, but most of the time there will be a very small amount of fuel being fed into the idle air supply. this is affected not only by the idle speed control (because that controls the level that the slide/butterfly bottoms out at), but also by the taper and level that the needle is set at and also the size of the main jet.
so in short; yes the main jet and needle position DO have a minute affect on the idle circuit's jetting mix, but it is very nominal.