I have to agree with Doc, those brown plugs in those really old (probably last updated in 1959) Champion charts don't represent modern conditions. The fuels are different, the combustion process is much more efficient, fuel injection is much more precise than carbs, etc. White with a slight tan tinge is closer to optimum these days.
Fortunately, too rich is better than too lean. Rich is wasteful and can contribute to carbon buildup and fuel washing of the cylinders, but lean can burn stuff up. As for mileage, at 80 mph and up I don't think I'd expect 40's, but 32 mpg is way low for a recent model TC/Cruise Drive.
Jerry
I would have to think the 32mpg would be where I'm at given the conditions of the ride yesterday, I DO have the 30T trans sprocket which spins the motor just a little faster.
My "normal" riding conditions will show about low to mid 40's mpg. I should have taken a shot of the OTHER side of the plugs, there is a "wash" on the other side that looks a lot lighter in color.
I think after running a few tanks of gas and checking mileage you can get a pretty good indication if you are running too rich or too lean. I would rather be on the rich side just a taste, if for nothing else to help cool the motor a bit.
With the cams and all I'm at about 100/100 on a 2010 and gotta say I'm pretty happy with overall performance and road manners.
As a side note, my 113 EVO has more power and torque across the chart, and I get BETTER gas mileage, go figure! Of course, nice heads, etc, etc. Not really comparing apples to apples.
Thanks to all for your comments!
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Topic: Nasty spark plugs (Read 3933 times)