How many times do you turn that screw out?

Lots of factors at play.  Fuel, elevation, jets, intake, exhaust, ambient temperature, and humidity are all involved.  You should set it according to your specific set of circumstances.  Here's a simple video guide the guys around here recommend whenever this question comes up https://youtu.be/YxpQjDQzX7g

cl492 wrote on 04/04/16 at 10:55:23:


Adjustments to your fuel/air ratio is not a universal setting - it must be adjusted by ear or meter.  What works on one bike does not necessarily work on another bike.  Elevation, float level, amount of ethanol in the fuel, humidity & temperature, type of air cleaner, etc. can all affect the setting.

As Verslagen indicated you can start at 1-1/2 turns out - which is in the middle of the adjustment range (At 3 turns out the screw is backed out to the maximum flow and additional turns out will have no affect.  I have posted 2 videos below that show how you "listen" to find the point at which your engine runs smoothest - which is the point you are trying to find.  You need to slow the engine idle speed down a bit to make this adjustment - as it is impossible to hear the change when the engine idle speed is up and the main/needle jet is supplying fuel to the engine.  Your bike MUST be fully warmed up to do this adjustement - setting the mixture with a cold engine will get you a setting that is too rich for a warm engine.

https://www.youtube.com/watch?v=YxpQjDQzX7g

https://www.youtube.com/watch?v=zm5mB3R8Ucw

If you can turn the idle mixture screw all the way in and the engine still runs - your pilot jet is too big.  If you have to turn the screw out more than 2.5 turns - the pilot jet is too small.