Quote:
Originally Posted by tubarney
Also, shimming the needle will not help you out below 5-6k. You need to turn the pilot screws out 1 turn.
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no...
rpm ranges vs carburetor settings have much less to do with each other than carb settings vs throttle openings.
The main jets control fuel at WOT. The needles control fuel at partial openings. The pilot jets control fuel at very small throttle openings.
The needles do make a significant difference under 5k because when you snap the throttle wide open, the slides open up gradually as the airflow increases. This is due to a pressure difference in the carb. The slides moving up slowly keeps a constant velocity of air through the carb. That's why this is called a CV carb; it keeps a Constant Velocity of air.
Read through that tuning guide I sent you in that other thread, tubarney. The method it suggests (which works well) for testing needle height is to get the bike putzing down the road at 3k in 2nd, then snap the throttle to WOT and hold it there. As you bike takes in more air, the slides will raise gradually. If your needle height is correct, this test will result in a smooth acceleration from 3k all the way to where the slides are completely raised and the main jets are in charge, which is around 10k.
Also, you do realize that turning the pilot screw out 1 full turn will result in a really rich idle that will bog right? You adjust those in 1/8 or 1/4 turn increments, not full turn increments. Leave those at the standard 2.5 turns out for now; the idle is perfectly fine to be running as close to a 14.7 AFR as you want because there's no load on the engine at that point. Besides, the pilot screws are at 2.5 turns out. If you get to 3.5 turns out, you need to go to a larger pilot jet. The OP's stock bike does not need a larger pilot jet.
If anything, the OP only needs to leave their stock setup for now, shim their needles with 1 washer, and then do everything else in the spring when they have more representative temps and can better tune their jetting. This will help their mid-range a touch for now without being too rich for when it warms up.