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On all my other bikes, and cars, commuting around 55 mph yields me the higher gas mileages. More agressive riding reduces the fuel mileage return. I've ridden this CBR for about thirteen fill-ups, and done a fuel mileage calculation each time. The MPG versus riding style is flip-flopped. If I commute the whole tank of gas at 55-60 MPH, straight and level freeway, mostly steady throttle, I get about 65 MPG. But when I go through most of a tank of gas on a day ride up in the mountain twisties, completely flogging the engine, pinning the throttle regularly, full throttle from stop light to stop light, etc. I am rewarded with 74-75 MPG! Any ideas why I am seeing these returns which seem to defy logic?
 

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Maybe it's because your right hand is off the trottle so you can "flog it" :D
 

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Maybe as the mechanical bits get a bit of the newness worn off they become more efficient. It is typical for vehicles to take some months to reach their best.

Maybe also, you are becoming more effective at using the brakes, the throttle and the bike in general as you become more familiar with it.
 

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Given that all things are equal...you should get the same mpg but you stated that you drive straight and through at 55 constant throttle weekdays and on weekends you do the wild thing.. If you read up on high milers (folks that strive for the highest mpg possible). A technique they do that increases mpg is called surging. Race up to high speeds then slow to a stop. A VW Jetta TDI got an estimated 95 mpg doing this.. Also including coasting to a stop, coasting down hill. If you do the surge coast thing on your morning commute you will be the target of a mad driver... Find your self a weekend and do your wild thing on your normal commute surge coast etc and see what happens.. My CBR is the alternative for my VW TDI. I get 50 mpg when in do a modified high miler technique EPA rating is 42. Once it gets warm weather I will try it on the CBR. Why bother. Diesel in AK is 5$ per gallon. Gasoline is 4.75$.. Fellow European owners I feel you pain .... We will some day pay you fuel cost


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High MPG ?????

On all my other bikes, and cars, commuting around 55 mph yields me the higher gas mileages. More agressive riding reduces the fuel mileage return. I've ridden this CBR for about thirteen fill-ups, and done a fuel mileage calculation each time. The MPG versus riding style is flip-flopped. If I commute the whole tank of gas at 55-60 MPH, straight and level freeway, mostly steady throttle, I get about 65 MPG. But when I go through most of a tank of gas on a day ride up in the mountain twisties, completely flogging the engine, pinning the throttle regularly, full throttle from stop light to stop light, etc. I am rewarded with 74-75 MPG! Any ideas why I am seeing these returns which seem to defy logic?
It's called volumetric efficiency. This occurs at peak Torque RPM +/- 500 RPMs. During normal operation during the week, the engine is operating below this point. When you operate the cbr in a spirited manor, your are operating in the volumetric efficiency range. :cool:
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