For what it's worth, and it's probably not worth much because I ran a Thundermax from the start, I was getting 30 mpg when brand new. I've got 2400 miles on it now and it's up to 41 mpg when 2 up. I can't say for sure, but I think the mileage gets better with break in and I know it got better when I tweaked my AFR's.

 

I agree, I have 8,000 miles now , my mileage got better the more i rode . if i stay of the wick i get 40-43mpg

 

My 07 FLHTCU only gets 33-35. I am not happy but do not know what to do.

Have been thinking of making it run a little more lean but who knows what i might FU in the process.

 

Getting 46 with my stage one 88"

 

My HQ 98"er gets 40~42mpg riding 2up, as long as we stay below 75mph. On a recent trip to Deals Gap, riding 2up, loaded w/gear... running 85mph steady, we got 35-37.

 

103" getting 44 at about 65-70, 39 at 75 an 40-42 around town if I consciously work on keeping the wrist outta it. If I dont, it can get as low as 36

 

After months of tweaking my PCIII's map, I'm at this point now in summer, about 5% lower in winter:

Highway, backroads, avg. 55mph: 50 mpg
Highway, avg. 65 mph: 47 mpg
City, numerous cold starts: 40 mpg

I'm fairly happy with this, but am still trying to better it. Just adjusted the map a bit leaner but haven't done any mileage checks yet. I can switch maps on the fly with two stored on the PCIII, and Map 2 is much richer, with values set for maximum cooling. So when the going slows, I just switch maps to cool things down.

You say you're getting 30-35 mpg, but under what conditions? Highway, city, combination, high speed? That makes a big difference?

 

I recently installed the Tmax. Just checked it today and got 32 MPG around town. That is about the milage that I was getting before te Tmax. I could lean the AF ratio but it runs so good, I think that I will just leave it the way that it is. The Tmax default is 13.2 AFR.