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sparkplug color too Rich? too lean?

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Ok so i just beefed up my drz400s (2001). I bought the JD jet kit used their pilot jet and installed the 160 jet. On top of that i bought the yoshimura RS3 full exhuast system (header and muffler). I removed the spark arrester. So took it for a desert run up to randsburg right next to red mountain here in southern cali. When i get home and start tearing down my bike i decide the check my spark plug. I noticed that the ground arm on the plug was kinda white. Now i know this is a sign of the motor running lean. Im going to try and click the needle up once to see if that will richen it up. Well to get the point, How can you tell if a motor is running lean or if it's running rich. I know you can tell by looking at the plug, but is there any other way?? Any info would help, thanks alot guys.:applause:

Any one going out to lucerne for the AMA race this weekend??

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Plug check wont work unless your running way rich. A 2 stroke plug check yeah would work looking at the plug but DRZ 400's are 4 strokes. You have to hear and feel what the bike is doing at decel and roll ons. Is it popping on decel? Does it stumble on acceleration?

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Which needle did you install - red or blue? I installed the JD kit with the following:

150 main

blue needle on 3rd position (cool temps around here this time of year)

25 pilot

I did the 3x3 and I've got a ProCircuit T4 slip-on.

I ride at 5000ft, and the above is spot on in terms of throttle/bike response. Have not yet however looked at the plug since the install

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The bike kinda strugles in mid range throttle. when i pass mid range i feel the torque kick in. when i decel, at times i will hear popping. I have heard that a little popping noise is ok. I am running the red needle, 160 main, and the pilot that JD supplied me with. I did the 3x3 mod. Tonight i should find out if a needle adjustment made any diffrence in performance. Any one have any jetting ideas for the pasadena area in california???

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