Check spark plug for correct A/F mixture.

[doj1975]

I just put a TFI unit on my bike last week. I tuned it the way the instructions said. I just wanted to get some info on how I can check my plugs to find out if I'm running too rich or lean. What should I look for to make sure my A/F ratio is where it should be. If there is any other ways to make sure I have it set right I am all ears. Thanks,:6:

 

[glider]

Many topics on plugs covered here.

Harley Davidson Engine Related Issues - Harley Davidson Community

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