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Help me read my plug

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Put about 100 miles on the 82 xr200r yesterday. 5000ft desert/mountain single track. For the first time I think I was hearing some detonation when I really loaded up the motor. Plug doesn't look horrible to me, but I'm new at air cooled motors. I think I'll raise the needle a position and see how it goes. Any input is appreciated.ImageUploadedByThumper Talk1401208972.373040.jpg

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Reading plugs is difficult today as the gas has no lead and the color is not always a good indicator, especially if you didn't follow a proper chop procedure.  Try Mikuni's Roll-Off Method:

 

"Roll-off Method:
This method is a good way to get the main jet either correct or within one size of correct. It is based on the fact that that as the throttle is closed, the air/fuel mixture richens momentarily. This normal enrichening can be used as a diagnostic tool. The test is started with the engine running at an rpm high enough to ensure that it is “on the cam.” Open the throttle fully and let the engine pull for several seconds. Then, quickly close the throttle to about the 7/8ths position. If the engine seems to gain power, the main jet is too small (lean). Fit a larger jet. If the engine hesitates as the throttle is rolled off, the main jet is too large. Fit a smaller one. When the main jet is correct,  the engine will continue to run smoothly and evenly as the throttle is closed. Note that a main jet that is far too rich or lean may cause the engine to misfire at full throttle."

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so when the guys at xrs only say read the plug there wrong then

i wonder how they stay in business

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