All you have to do is adjust the idle as low as it will go. Then turn the idle mixture screw in or out to find the highest speed, this will be the best mixture for idling. Usually the engine will try to die as the screw is turned in, turning it out will increase the idle speed up to a certain point. If you end up turning the screw out more than about 3 turns you probably need a larger pilot jet to get it set to optimum. (he ideal number of turns out is 2) Then reset the idle to not less than 1100-1200 RPM.

drannonb wrote on 04/26/18 at 14:25:00:


You are listening for the "tone" and speed of the idle.  Turn the speed way down.....around 800 rpm.  Then move the screw in and listen to the speed - as the screw goes in the engine should begin slowing down and it may even stall.  (If you can turn the screw all the way in and the engine still runs smoothly - your pilot jet is too big).  Then turn the screw out and the speed should increase, and at some point the engine should sound "fat".....the sound of an rich mixture is just a bit less different - the engine may begin to slow down.  (If the screw goes out more than 2.5 turns without sounding fat.....the pilot jet is too small).  The ideal mixture is somewhere between the lean and rich positions and should provide a smooth/even idle.  If you find the bike pops and bangs excessively and makes a loud bang when you turn it off....you can try opening the screw another 1/4 turn and see if it helps - but don't open it much more than that or the bike will run too rich.

Then.....adjust the idle speed back up to 1,100 - 1,200 rpm - high enough to keep good oil pressure at idle and prevent the bike from stalling when you close the throttle quickly.

These videos may help.....the Savage has a "fuel" mixture screw and turning it out makes the mixture richer.

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

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

On any carb.....I always use 1.5 turns out from lightly seated as my starting point for carb adjustments.

Mikuni claims that when doing the carb adjustment.......if you have to turn the screw out more than 2 turns to get a smooth idle - you need a larger pilot jet.  If the screw is out less than 1.5 turns to get a smooth idle.....you need a smaller pilot jet.

There may be a bit more leeway than that for our mildly tuned street bike - however you should never turn the screw out more than 3 turns as the tapered portion of the needle is out so far that additional turns won't make any difference....and you need a larger pilot jet - and it you can turn the screw all the way in and the engine still runs....your pilot jet is definitely too big and you need a smaller pilot jet.