2009 GS lean mixture, harmful???
While checking valves on my 2009 1200GS at 40,000 miles, I noticed spark plugs showing a lean mixture. I have a K&N installed but no other change and realize manufacturers have clean running as a priority. Question is: are other riders showing light spark plug coloring which is kinda normal or Is this something that needs attention and if so what? I have not noticed any spark knock when pulling at lower rpm.
Thanks for your time in responding.
Arroyo Grande, CA
R1200GS, R80RT, DR650