What's your best motorcycle MPG?

[theycallmeebryan]

Hello all. My first post here. I have been browsing the boards for quite a long time.

I bought a completely stock 2003 Kawasaki Ninja 250 in summer of 2008 (with 885 miles on it!) and have been riding it as much as possible in order to save on gas. I commute primarily on the highway to college and to work, so the bike most of its life is ridden at 75-80mph.



Here is a gas log since i have bought the bike:



Aerodynamically, the bike is stock.

The stock final drive on the Ninja 250 is 3.21. On 07/16/08 i installed a 15 tooth front sprocket to lower the final drive to 3.00. At the same time, i replaced the tires with taller profile touring tires (effectively also making the gears taller). Stock, the ninja 250 speedo (and likewise odometer) read about 8-10% more than actual. With the new tires, that error was brought within 1% roughly.

On 08/26/08 i installed a 39 tooth rear sprocket, lowering the final drive to 2.60. The bike has just enough power to keep me going at highway speeds. Above 60mph i always ride in a tucked position (i have mastered a comfortable tuck that i can sustain for over an hour straight). At 75-80mph, Even raising my head up from behind the stock windscreen drops my speed about 2-3mph with a constant throttle position.

I would also like to note that the 3 60's mpg points in my log reflect fuel periods with "Spirited driving" with a group of friends. I think its pretty neat that I can pilot the little ninja more aggressive than normal, yet still yield over 60mpg.

[philip1]

my last bike was a VT500 tuned up a bit top speed was 129mph and it would lean forever. My best milage was 61mpg and worst was 56mpg

[Diesel Biker]

Hello, I'm Dave, I built a Bio-diesel Honda with a Ruggerini RD 211 Diesel engine. My best milage to date has been 128mpg, I average 65-85mpg with theturbocharger installed.

YouTube - Turbocharged Biodiesel Honda Motorcycle Big Taco Mini Bike

[beatr911]

Big Red now has just over 203,000 miles and runs like a top. I've been averaging just over 54 mpg with my commute which is about 10 miles at 40-50mph and the remaining 20 miles at 60mph, one way. This year I'm experimenting (again) with going as fast as I can without standing out enough to get a ticket which is about 70-75mph to see what the difference in mileage is. I think last time mileage dropped 4 or 5 mpg. The chassis and engine really feel in thier element at about 4500 rpm which is about 80mph. Top end is an indicated 125 mph which is limited by aerodynamics, or the 108horsepower.

Mods to improve economy are: advanced spark timing by 4 degrees, cut down stock windshield so helmet is just out of windshield disturbed air, warm air induction to airbox, dropped carb float level by 10mm, increased plug gap from .025" to .035", advanced exhaust cam by 7 degrees for more mid-range, used a 3/4" hole saw and drilled out the interior baffle in the exhaust (much better sound without loundness), synthetic oil in shaft drive unit, smaller EX500 mirrors, use approximately 132:1 of filtered used engine oil in the tank (because otherwise it's BTUs just thrown away).

Biggest improvement by far was ajusting the float level down. I gained about 7 mpg just from this. These bikes are known to run very rich and this confirms it for me. There is a guy in florida that makes a jet kit for it for about 50 bucks and all he does is lean out the rich spots to even out the mixture. I might do that in the future.

Gearing is bad on these bikes as well but not as bad as some. About 3600 rpm at 60mph isn't too bad but this is a 1000cc engine. The same guy as above makes a gearing change kit for these but to drop 600rpm costs about $450.00 and improves mileage by just under 5 mpg - really long payback on that one.

Live long and prosper!

[beatr911]

Originally Posted by Diesel Biker

Hello, I'm Dave, I built a Bio-diesel Honda with a Ruggerini RD 211 Diesel engine. My best milage to date has been 128mpg, I average 65-85mpg with theturbocharger installed.

Nice job on the diesel! Maybe we'll see a good production one someday. If my motor ever dies, diesel converison is what I'd consider doing.

[MetroMPG]

FYI, a couple of Vespas (2007 250 cc) and a Hayabusa competed in the fuel economy rally at the Green Grand Prix in Watkins Glen NY last weekend. (See link for details of route/speeds, etc, but the avg speed was probably mid/high 40's mph).

Vespa: 86.6 mpg

Hayabusa: mid 50's mpg

[dcb]

Originally Posted by MetroMPG

Hayabusa: mid 50's mpg

LOL, 0–60 mph: 2.47 seconds AND 50mpg

[dcb]

Bikes are just awesome

[janvos39]

The Kawasaki ninja with over 70 MPG. A very nice achievement. It shows that a lot can be gained by doing the correct gearing. I wonder what is now the RPM at a speed of 75 Mph ? Are you planning any aero mod´s for the Ninja? At this level of MPG you probably can detect very quikly how much an improvement brings.Last qustion on the Cd*A do you have any info on that e.g. a good picture from front or back for the surface area?
It would be nice if we can calculate the engine efficiency when the air resistance and the rolling resistance is estimated. Good work keep on going.

[theycallmeebryan]

Originally Posted by janvos39

The Kawasaki ninja with over 70 MPG. A very nice achievement. It shows that a lot can be gained by doing the correct gearing. I wonder what is now the RPM at a speed of 75 Mph ? Are you planning any aero mod´s for the Ninja? At this level of MPG you probably can detect very quikly how much an improvement brings.Last qustion on the Cd*A do you have any info on that e.g. a good picture from front or back for the surface area?
It would be nice if we can calculate the engine efficiency when the air resistance and the rolling resistance is estimated. Good work keep on going.

My rpm in 6th gear is about 950rpm per 10mph. At 75mph my engine spins at about 7100 rpms. With stock tires and gearing, at 75mph the engine spun at about 8500rpms. My bike now does not burn any oil (very very tiny amount if any) after long cruises.

Yes, i am planning to do some aero modifications to my bike. I am currently working in a program called SolidWorks to come up with the best, practical design.... this is my daily driver and i need it to be usable.

After looking at the 125mpg trike on the front page (its powered by a Ninja 250 motor and transmission), i have seen the potential of my platform breaking the 100mpg mark with better aerodynamics.

This is really the only picture i can find of the front of a pre-2008 Ninja 250.