Cruising AFR for Hi Performance Baggers

[kdietz]

In the cruise zone, I've tried everything from 13.8 to 14.4 with my 107" oversquare '06 Ultra build (120tq/110hp)....I'm getting better mpg at 14.0 than 14.4...

Are others with higher performance builds finding the same results?

[FLTRI]

Can you specifically describe the "cruise zone"? Sometimes when leaning the mixture it takes a bit more TP to get the same speed. This can push the TP into richer cells causing a loss in mpg.
Bob

[kdietz]

Can you specifically describe the "cruise zone"? Sometimes when leaning the mixture it takes a bit more TP to get the same speed. This can push the TP into richer cells causing a loss in mpg.
Bob

Bob, I think of the "cruise zone" as 30 to 50 MAP from 2250 to 3500rpm

[Don D]

Not him but I would think that is closer to a downhill run or idle

[FLTRI]

Bob, I think of the "cruise zone" as 30 to 50 MAP from 2250 to 3500rpm

So from this I assume you have a SERT or TTS?
So are you adjusting the AFR from the AFR table or are you measuring the tailpipe AFR and making VE changes from there?
Have you had the VE tables recalibrated to the AFR table?
Bob

[kdietz]

I'm using a SERT and Twin Scan II+....I'm cruising at 70mph at 35-40Map, 2800rpm and 10% TP

VE's are dialing in and the bike runs great....I'm just finding that I can get better MPG in the 13.9 to 14.0 range than at 14.2 to 14.4

[FLTRI]

VE's are dialing in and the bike runs great....

Not quite sure what you mean by this? How are they doing this?

[kdietz]

VE's are dialing in and the bike runs great....

Not quite sure what you mean by this? How are they doing this?

Sorry...typo...The VE's are dialed in with the TSII+

[FLTRI]

Just trying to figure why less fuel = more mpg, unless you are really not in the leaner AFR area of the fuel map you believe you are.

[kdietz]

Just trying to figure why less fuel = more mpg, unless you are really not in the leaner AFR area of the fuel map you believe you are.

I agree......my data logs show where I'm doing my highway cruising so I feel like that's accurate.

With heavier bikes....Ultra Classics.....is there a point where you have to twist more at 14.4 and actually end up burning more fuel and creating more heat to keep the same speed as at 13.9-14.0 with less twist?

On the same line as why I get better mpg at 70mph in 5th gear than I do at 70mph in 6th gear.....and why I get better mpg with 100% fuel instead of 10% ethanol fuel?

[Don D]

Thanks for the clarification