I have an '03 Baja, and MBRP slip-on, a DYNO Jet Kit, and a UNI in the stock airbox. I am on the second clip down with a DJ190. Two turns out. I went from a DJ180 to a DJ190 and noticed some pick-up in the mid-range. The plug looks basically the same. I called Dyno Jet and he said the 180 was recommended but could go to a 190 if I felt better. How do you know if you're jetted properly though? It seems to pull hard through all the gears and no back-firing when I back off the gas. I'm sorry if I sound stupid but this is my first 4 stroke. Any help would be appreciated.

 

depending on the fuel you are running your plug should be a tan-ish color. if your fan is constantly comming on it may be to lean. if you run 100 or higher octane it is a bit harder to read your plug. if there is no lean popping on deceleration you should be fine , but if you want to be safe make sure your plug is not completely white , due to air density you may get a different plug reading IE on a cold morning you might get more of a leaner reading ,thought i could help ... been there done that

 

Ya...I agree with what ANNIHILATER said, also the most accurate way to check spark plug color is to run the motor in the throttle range you are wanting to test, mid , wide open, etc for at least 15 to 45 seconds, then pull in the clutch, turn off the motor, stop and pull the plug to check color, if you ride at WOT then putt around and idle the motor the the color will change rather quickly, and give false readings.......hope this helps and Welcome the best Bomb forum around.........