Home Forums Tech Talk Tuning the idle jet with EGT Reply To: Tuning the idle jet with EGT

Oscar Aguilera

havent been on here in a while…if you are tuning a non programmable ignition motor with a shifter type carb…ie mikuni,,,delorto…etc i was taught this method


my top end goal egt would be 1250 for me on my one motor…(i had another motor that liked 1300)  to play it safe go for 1200.

i would sit in the kart with the motor off and the aif filter off and try to hit 1/2 throttle with my foot while some one verified if i was at half throttle…i would train myself to hit this spot as consistently as possible…then 3/4 throttle…then 1/4 throttle.  verifying each time till i could get a consistent feel.


i would then go on the track and about just past half way down the straight…i would go from full throttle back to 1/4….look at the tach and remember the number.  you are looking for around 1050.  then on the next lap after hitting full throttle down the straight just past the halfway point…i would back off to 1/2 throttle…remember the temp…i was looking for 1100….at 3/4 throttle i was looking for 1150.  if your high end temp is higher you adjust your range accordingly…you are looking for 50 degree increments going backwards from your high end of the straight desired temp.


check the plug…learn to read it…verify…get a feel for the egt your motor likes with your particular gauge and you will be able to better tune your motor.  it takes time..the ability to read the gauge…and a few uninterrupted laps.  this helped when traveling or tuning the motor for changing weather conditions…which you always chase.


just my opinion