bitabur
Registered
Tonight I stopped for gas, and after resetting the trip meter, I tried to figure out how to get the best mileage at different speeds.
I've heard here before that the engine seems to be the most efficient at about 4000-5000 rpm, which I tested, and I found that indeed, on the freeway, cruising at an indicated 70-75mph, I get better mileage in 5th than 6th gear. Ok, people were right.
Since that test, I've tried to keep the engine in roughly that rpm range most of the time when I'm traveling steady speed, figuring it was the most efficient. Tonight I found that my bike seems to get the best mileage in 5th gear (at low speeds even 6th gear) all the time, even down to an indicated 25 or 30mph, with the engine under 2000 rpm.
I have a hypothesis about this, but first, is there something about the 5th gear fuel map that would make it more efficient? I always heard that 5th/6th was richer because of compensation for forced air into the intake, which would make it less efficient, right?
My hypothesis is that at lower speeds, where aerodynamics don't matter as much, simply turning the engine slower saves fuel, as long as you're keeping a steady hand on the throttle and not bogging the engine to accelerate. On the other hand, at higher speeds, the engine needs to fight much more wind resistance, and because the engine is more efficient at higher rpm, overall mpg is better with the engine revving up a bit more.
Does any of this make sense, and has anyone else had the same results?
PS. My absolute most efficient, steady speed freeway cruising, tucked-in mpg is about 44, while for short spirited stints I've had it down below 25. My average since I've had the bike (haven't reset trip1) is about 33 mpg. I weigh ~280 lbs without gear, and always run 87 octane.
Does this sound about right or should I get a PC and get a few maps made?
I've heard here before that the engine seems to be the most efficient at about 4000-5000 rpm, which I tested, and I found that indeed, on the freeway, cruising at an indicated 70-75mph, I get better mileage in 5th than 6th gear. Ok, people were right.
Since that test, I've tried to keep the engine in roughly that rpm range most of the time when I'm traveling steady speed, figuring it was the most efficient. Tonight I found that my bike seems to get the best mileage in 5th gear (at low speeds even 6th gear) all the time, even down to an indicated 25 or 30mph, with the engine under 2000 rpm.
I have a hypothesis about this, but first, is there something about the 5th gear fuel map that would make it more efficient? I always heard that 5th/6th was richer because of compensation for forced air into the intake, which would make it less efficient, right?
My hypothesis is that at lower speeds, where aerodynamics don't matter as much, simply turning the engine slower saves fuel, as long as you're keeping a steady hand on the throttle and not bogging the engine to accelerate. On the other hand, at higher speeds, the engine needs to fight much more wind resistance, and because the engine is more efficient at higher rpm, overall mpg is better with the engine revving up a bit more.
Does any of this make sense, and has anyone else had the same results?
PS. My absolute most efficient, steady speed freeway cruising, tucked-in mpg is about 44, while for short spirited stints I've had it down below 25. My average since I've had the bike (haven't reset trip1) is about 33 mpg. I weigh ~280 lbs without gear, and always run 87 octane.
Does this sound about right or should I get a PC and get a few maps made?
