jetting query....... help please
Posted February 23, 2007 - 11:29 AM
i have just fitted an aftermarket fuel screw and would like to know which way to turn to make more rich?
i have also fitted 168 main 48 pilot and adjustable needle with circlip on center groove. she starts fine but cuts out when throttle opens to quick. mid range is fine but top end is spluttery/wont pick up.
the spark plug is white so i know the mixture is lean and when revved up the airbox seems to make a sucking type of sound.
the fuel screw is currently 1 1/2 turns out.
i will try moving circlip down one groove to make rich and adjust fuel screw to make rich, but if this does not sort out lean mixture shall i fit a 170 main.
thanks for any suggestions
btw is 06 wr450 0 to 4000 alt and cool temp
Posted February 23, 2007 - 02:30 PM
Posted February 24, 2007 - 07:07 AM
This is probably due to the AP circuit. You'll need to tune your leak jet and the pump timing. Check the sticky's in the 250F forum for the FAQ.
...she starts fine but cuts out when throttle opens to quick.
Not sure; the symptoms sound too rich, but I would guess that you need to go richer, still, only because I'm guessing it's cold and wet over there (however, the cold requires richer jetting while the wet requires leaner jetting). Fortunately, the mj is the easiest to change. try a 165 and then a 170 and see which is better.
...mid range is fine but top end is spluttery/wont pick up.
Posted February 24, 2007 - 07:12 AM
Good Luck !
Posted February 24, 2007 - 07:02 PM