I have a Power Vision tuner and it has a global setting where you can retard or advance the timing across the whole map from idle to WOT.

 

Thanks for the input. Yes, plenty of smile! Just wish for a few more miles, but looks like I will have to get better control of my need for speed to do so. Will removing the Catalytic increase/decrease fuel economy?

 

I decatted and put SE Cannons with a Dyna jet with a box tune . Lost 1 to 2 mpg but a lot cooler and snappy on the throttle. Maybe that's the loss . Lol

 

Our 2010 we bought "pre-owned" in 2013 has averaged 36.1 over the last 15K miles. Very little highway miles, mostly 2-up. Cat is gone, std pipes.

 

I was up on the blue ridge parkway last summer for a couple of days . pertty much running the speed limit. Averaged 45. MPG

 

You have a 2017 with the M8, it will be interesting to hear what others with the M8 are getting. You really can not compare to the rest of us with older Twin Cam's. I would guess from what I saw on longer test drives. The 2017 Tri Glide was getting about 27 mpg with quite a bit of 60-75 mph. I filled it up before taking off, then topped back off after a 150 mile with 5.5 gal. I was not riding all interstate, just normal county road, and some interstate. Note at that time the 2017 was a new demo with 10 miles on it when I started out. I am sure it will get better after some break in.

 

I'm getting 33 to 37. I have about 1800 miles on it. The first couple of tankfuls, when it was new, I got about 28.

I seldom ride faster than 75 except for when I get the urge to twist on it for short distances. I do tend to twist the throttle more than necessary running around these Tennessee hills. What's up with feeling like a kid again?

 

Another factor to consider is, if you are running into a head wind, your mileage will drop. The fenders act like parachutes.

On a trip several years ago, running 1 up with luggage, I averaged 32 to 36 mpg. Until I hit a head wind going south on I-44 in Oklahoma and my mileage dropped to 20 mpg.

When running above 70 mph your mileage will drop some.

 

I always use additive Stabile 360 do not trust fuel quality, once in a while I will add 104+ just to clean off injectors. 34 to 38 MPH in Pennsylvania and that average is over 4 years. travel safely Fred

 

Both '12 & '13 Tri Glides were right about 30mpg when doing 2 up riding. They did a bit better when my wife rode it solo. We would fill up at 150 miles to be safe. New '17, again doing mostly 2 up riding has been getting closer to 35mpg, so we fill up around 175 miles. Wife hasn't done much solo riding on the '17 yet.

Funny, last time I rode the Blue Ridge I had the same experience as PRrdglide. I had a Road King that normally got around 40mpg, but got an easy 50+mpg on the Parkway. Gotta be better gasoline up that way.