MPG curiosity

[250rr]

Best fuel economy on my '10 250r = 62 mpg. Best on my 750ss = 64 mpg.

Even taking into consideration the Ninjette has a carburetor and the Duck is FI, does anyone else find this surprising?

[fishdip]

Originally Posted by 250rr

Best fuel economy on my '10 250r = 62 mpg. Best on my 750ss = 64 mpg.

Even taking into consideration the Ninjette has a carburetor and the Duck is FI, does anyone else find this surprising?

I'd ask what driving u did as 75 on the interstate at a hi rpm will use more fuel

[250rr]

Originally Posted by fishdip

I'd ask what driving u did as 75 on the interstate at a hi rpm will use more fuel

Yes, in both circumstances it was freeway riding. Moderate traffic. I will say that the Ninjette mpg test was done at around 45 degrees, the Duck at around 70 degrees.

[fishdip]

Originally Posted by 250rr

Yes, in both circumstances it was freeway riding. Moderate traffic. I will say that the Ninjette mpg test was done at around 45 degrees, the Duck at around 70 degrees.

try another test in town I think the 250 will do better.

[Live2ride]

my 09 250 got 50mpg and so did my 07 zx6r. My current ride, an r6r gets 35mpg...

[250rr]

Originally Posted by fishdip

try another test in town I think the 250 will do better.

Although I no longer have the 'Jette, I had already done that. Worst mpg was high 30's. Same with the Dew Kitty. Just surprising to me. I am very happy with the Dew Kitty mpg, I must say!

[Jiggles]

My k1300s gets better mileage than my 250 and I drive them similar. I never need to go over 5k rpms on the bmw while I never need to go over 13k rpms on the ninjette.

[outasight20]

My FZ6 returns 55 when babied on the highway, and 45 when driven hard with a mix of city and highway. My old '03 250 got about 60 highway and mid-high 40's mixed, so not much different.

[Brother Michigan]

If you're anything like me, you can't help but wring the heck out of your Ninjette even when you're trying to be economical, which is obviously disastrous (relative term) for the fuel economy

[Jiggles]

Originally Posted by Brother Michigan

If you're anything like me, you can't help but wring the heck out of your Ninjette even when you're trying to be economical, which is obviously disastrous (relative term) for the fuel economy

The nice thing is though that its nearly impossible to get less than 40mpg

[Motofool]

Originally Posted by 250rr

Best fuel economy on my '10 250r = 62 mpg. Best on my 750ss = 64 mpg.

Even taking into consideration the Ninjette has a carburetor and the Duck is FI, does anyone else find this surprising?

Remember, for flat open roads, fuel is used only to overcome forces that resist movement.

Things that favor the Ducati 750 SS, regarding economy:

-Fuel injection = Less restriction to air intake

-Engine's V configuration = Less aerodynamic resistance

-Two valves per cylinder = Less cam effort + slower mix flow

-Air cooling = No water pump or fast-circulating coolant or radiator facing the airstream

-Lower max torque / power rpms' (~6K / ~8.3K) = Less mechanical internal friction and parts' accelerations

Things that favor the Ninjette, regarding economy:

-Higher compression ratio (11.6:1 vs 9.0:1) (possible due to liquid cooling) = Higher thermal efficiency

"The compression ratio of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity.
.........
A high compression ratio is desirable because it allows an engine to extract more mechanical energy from a given mass of air-fuel mixture due to its higher thermal efficiency. This occurs because internal combustion engines are heat engines, and higher efficiency is created because higher compression ratios permit the same combustion temperature to be reached with less fuel, while giving a longer expansion cycle, creating more mechanical power output and lowering the exhaust temperature."

http://en.wikipedia.org/wiki/Compression_ratio

[250rr]

Originally Posted by Motofool

Remember, for flat open roads, fuel is used only to overcome forces that resist movement.

Things that favor the Ducati 750 SS, regarding economy:

-Fuel injection = Less restriction to air intake

-Engine's V configuration = Less aerodynamic resistance

-Two valves per cylinder = Less cam effort + slower mix flow

-Air cooling = No water pump or fast-circulating coolant or radiator facing the airstream

-Lower max torque / power rpms' (~6K / ~8.3K) = Less mechanical internal friction and parts' accelerations

Things that favor the Ninjette, regarding economy:

-Higher compression ratio (11.6:1 vs 9.0:1) (possible due to liquid cooling) = Higher thermal efficiency

"The compression ratio of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity.
.........
A high compression ratio is desirable because it allows an engine to extract more mechanical energy from a given mass of air-fuel mixture due to its higher thermal efficiency. This occurs because internal combustion engines are heat engines, and higher efficiency is created because higher compression ratios permit the same combustion temperature to be reached with less fuel, while giving a longer expansion cycle, creating more mechanical power output and lowering the exhaust temperature."

http://en.wikipedia.org/wiki/Compression_ratio

Good stuff. Thanks! I had never considered the positive benefits of only two valves per cylinder!

[KawiKid860]

I'm glad we have Motofool here to be all smart and stuff.

Haha on my 500 the lowest I ever got it to by riding hard was 47mpg and I really had to try, usually 50-53 mixed commuting year round and 65+ on the highway, my highest being 68. That's with average speeds around 80mph not tucked in or anything.

On my F4i my highest was 42mpg doing the same ride that gets me 65 on the ninja, lowest so far has been 35 and I rarely ever get above 40. It really sucks because it's so much nicer to ride than my ninja and I've put nearly 2k miles on it since I got it, and only about 80 miles on the ninja since then.....