Fuel gauge on reserve

[FJR Bill]

The difference in air resistance is pretty negligible, the real biggie that saves you fuel in the hot temps is less oxygen in the hotter (like you said, less dense) air. The fuel management knocks back the gas and we get better gas mileage.

And the same reason the bike feels like it has extra kick in the pants on a 55 degree day.

Nope. Wrong on this one. If you are talking max speed or dragstrip times then yes, air density has a big effect on max horsepower in the way you describe it as the engine is pumping as much air (and gas) as it can and so a limiting factor in engine performance is air density.

But not running at WFO, or max hp everything is different and air density's effect on engine performance doesn't matter anymore. For example: if it requires 16 hp to run your bike at a steady speed of 70mph then it takes so much gas (and and whatever amount of oxygen) to make that 16hp. No matter what temperature it is. Your engine is 'throttled' and not using all the available air that it could. But with less dense air, and therefore less air resistance, it will now require LESS horsepower to maintain that 70mph and therefore less gas (and) oxygen to make that horsepower.

Skooter NAILED IT!! We are talking about efficiency during less than Max HP performance usage. The thin air at higher altitude results in less drag and improved MPG. This is ONE reason aircraft climb to high altitudes for long flights. The max engine horsepower is reduced to cruise power not max and the thin air results in significant MPG performance via less wind resistance...Pilots (or the owners) calculate optimum cruise altitude and airspeed for max efficiency while cruising. Skooter is a genious!! Bill

 

[SkooterG]

Skooter is a genious!! Bill

Ha ha!

Good thing you didn't post this on a Friday. The dogpile would have been so immensely epic they would have run your poor (but very wise) butt out of here. :lol:

 

[phroenips]

Skooter is a genious!! Bill

Ha ha!

Good thing you didn't post this on a Friday. The dogpile would have been so immensely epic they would have run your poor (but very wise) butt out of here. :lol:

But he called you a 'genious' not a 'genius'...it was clearly a side handed insult!

 

[JR'SFJR]

On a test with extra gas along and 45 mpg average on the readout, the light came on at 215 and was running out at 285.

 

[Fred W]

Whatever the reason, I have definitely noticed extra miles per gallon in the latest heat wave we've been having. I typically get 40-42 mpg but have been getting 45 and higher. And that is two up, all three bags and a PCIII squirting raw fuel in the intake!

 

[RadioHowie]

Whatever the reason, I have definitely noticed extra miles per gallon in the latest heat wave we've been having. I typically get 40-42 mpg but have been getting 45 and higher. And that is two up, all three bags and a PCIII squirting raw fuel in the intake!

Fred, I just gotta ask.....how does someone from the Live Free or Die State define "Heat Wave?"

 

[wheatonFJR]

Whatever the reason, I have definitely noticed extra miles per gallon in the latest heat wave we've been having. I typically get 40-42 mpg but have been getting 45 and higher. And that is two up, all three bags and a PCIII squirting raw fuel in the intake!

That's because Skooter sez that the air density is less in the heat, therefore you are pushing less molecules out of the way as you go down the road. Either that or he said you were dense...what???

 

[Fred W]

Whatever the reason, I have definitely noticed extra miles per gallon in the latest heat wave we've been having. I typically get 40-42 mpg but have been getting 45 and higher. And that is two up, all three bags and a PCIII squirting raw fuel in the intake!

Fred, I just gotta ask.....how does someone from the Live Free or Die State define "Heat Wave?"

When the snow doesn't stick. You can also tell 'cause the pickup trucks take the plow blades off.

Whatever the reason, I have definitely noticed extra miles per gallon in the latest heat wave we've been having. I typically get 40-42 mpg but have been getting 45 and higher. And that is two up, all three bags and a PCIII squirting raw fuel in the intake!

That's because Skooter sez that the air density is less in the heat, therefore you are pushing less molecules out of the way as you go down the road. Either that or he said you were dense...what???

Probably both.

Could also be that your tires get so much hotter and the air expands in them more. So, it's like you inflated them to 45 psi cold.

Or it could be that the gas is cold when you pump it up from the underground tank. Then as you ride along it expands as it warms up. It's like free gas!

 

[dcarver]

Does this mean phatboyz get less mpg than thingayboyz?

 

[ScottyUSN]

And here I thought I was doing good with the summer heat mileage up to about 42mpg.

I did push it (for the first time yesterday.. I was on reserve at 160 (nomrla for my bike), computer clocking 42mpg average on that tank. At the 250 mile mark set on the trip, I turn a corner and lose power....

I'm on an AE.. Awe ****, 3 miles to my favorite no ethel gas station or 7-11 in a Qtr mile..Rolled the dice and did the 3 miles with every turn (even lane changes)causing fuel starvation and calling me a dumb ass for not stopping at 7-11.

Made it the 3 miles and added 6.3 gallons.