2005 ultra,,, last two tanks have been 38.9 to 39 mpg ,, usually ge y42.5 to 43.2 plugs look good , 91 octane from the same place all fill ups ,,no leaks ,, no change in riding habits,, any ideas for the loss in mpg,
thanks

 

Summer gas is a different formula.

Higher average speed.

Thinner air

I'm not an expert, not even experienced, just dealing with the same issues here, but my last trip was in Canada and could not really figure out how many gallons as sitting at the pump I did not take the time for the liter to gallons conversion and just estimated. But I have noticed here, that my winter mpg is usually better than my summer mpg. I record it on a phone app so it shows up pretty clearly.

 

1 US gallon = 3.96 liters




Imperial gallon = 4.54 Liters.




MPG is subject to many variables.

if this is a trend, try a fuel system cleaner additive- the injectors may have a little junk in them preventing atomization.




mike

 

Thank you. I knew the conversions, but just estimated in my head instead of using the phone calculator to confirm my estimates. I used the For instance 9.1 liters and I quickly estimated 2.2 gallons. Why, instead of 2.0? Just did. That would have lowered my mpg by a few miles per gallon, so it showed 39 mpg when I actually got closer to 42. But I was on vacation and not being **** about mpg.

Back to topic, having app'd my mpg for several years, I do find that my summer mpg is usually several miles per gallon less than my fall and winter mpg.

Do I ride faster...maybe
Is the gas different...yes
Is the air drier, warmer...yes.

Am I wearing less clothes..yes

 

Doesn't matter to me, but just in case you want an accurate conversion: 1 gallon = 3.785 liters

 

my MPG vairy a huge amount if i check it often. usually dont. have gotten as little as high 20's and high as mid 40's depending on how i ride.

wind will make a big diff in it even w/ same route, habit, fuel ect. i took a trip cpl months ago and lost 80 miles to a tank in heavy cross wind. picked right back up once the wind died

 

Hills and winds have netted as low as 32mpg riding 2 up. No wind, but hills, and netted 42mpg riding 2 up.

 

My average for two years of riding is 42.9. My worse mileage was on May 3, this year coming home from Sand Point, ID. I rode into a 25 knot wind. I even turned down onto SR 28 through Odessa hoping to get into shallow canyons and dodge the wind. My mpg dropped to 35.6 mpg from Airway Heights to Ellensburg, 175 miles and 4.91 gallons. At first I was worried, but the next tank was 41.7 and that was the I-90 freeway race home.

Even speed does not seem to rob mpg as much as riding into a wind will.

 

I'd be happy just to get 38. The best I've ever gotten was 36 mpg.

SugsPa

 

I average anywhere from 38-46 depending on many variables. As long as there's no soot in your pipes/on plugs your not burning rich.......