Fuel Mileage

[ksquared]

I'm riding a new R3T, which I love. It's far and away the best bike I've ever had.

I only have about 1,300 miles on it, however, I've noticed something peculiar with the fuel mileage. Up to about 65 MPH, I get nearly 40 MPG, which I consider quite good for the weight, power and size of the engine.

However, once over 70 or so, the mileage drops precipitously - so much so that I thought A. I'd sprung a gas leak or B. I was in 4th gear instead of 5th. I'm not kidding - my mileage dropped to about 28, or a little less.

Is there something about the fuel mapping that would cause a steady state 80 MPH to guzzle fuel at 150% of the same consumption at 70 MPH? Is there anything that can be done about it? I wouldn't mind improving it some, but I really don't want to hamstring the bike either - that torque is addictive!

I don't have a TuneBoy or Power Commander, nor any other fuel processor. I also don't have the GTI Pro or any such device. Bike and exahust are stock - and likely to stay that way.

I know it's likely to ease up a little as the bike gets broken in and the mileage will improve a little - but I really think that this is going to take more than just "easing up". The idea of getting only 140 - 150 miles on a 5.8 gallon tank at a steady 75 - 80 MPH is really unacceptable.

Thanks for any input.

 

[TriumPhil]

KK, you ask a good question, but do you really think that approx 30 mpg at a steady 75-80 mph is unreasonable for a nearly 800 lb bike? Many cars' fuel ecomomies suffer direly over posted highway speeds, too!

 

[HellFire]

Well yea..... the way it's tuned is to pass EPA requirements. The EPA doesn't take into account full throttle or 70+ MPH. It's leaned to pass emissions, just like a Corvette. Drive it like granny and she'll eek every mile out of that drop of fuel ... open it up and it's a whole other story. But once you start playing with the performance like most of us have, and mileage is out the window anyway. I have a MINI Cooper that only gets 19mpg ... 225hp at the wheels from a 1.6L, but the mileage suffered a little. Kind of a trade-off .
My R3 is a little better ... around 25mpg ... and the gas is cheaper .

 

[rainman]

i got a little over 11000 miles on my r3t and run betwween 70-80 mph on average and get around 35-36mpg all stock

 

[ksquared]

KK, you ask a good question, but do you really think that approx 30 mpg at a steady 75-80 mph is unreasonable for a nearly 800 lb bike? Many cars' fuel ecomomies suffer direly over posted highway speeds, too!

Actually, I consider it terrible, since my Boxster S will get 28 MPG on the highway at 80 MPH. 3,000+ pounds; 262 HP.

My motorcycle should do better.

 

[TriumPhil]

Does your boxster have 4" pistons and will it go 0-60 in 3 seconds?

If you wanted a frugal machine, KK, you bought the wrong motorcycle.

I am certain that if you seek out an optimal tune for fuel efficiency and then ride your Rocket like you're 30 years older than your actual age, you will be sure to get much more acceptable results!

 

[Molinoman]

You also have to remember the aerodynamics of the Rocket (any regular cruiser/tourer motorcycle for that matter) are not very condusive to getting great mileage, we're probably lucky to get what we get.

Also I got 38.5 mpg when I was going 90+ up to Nashville in 2007 for RAIII, but I had "supposedly" 140 HP to get it up there, maybe with the R3T gunning in at 106 HP it may have had to "work" more/harder to get it to that speed. Just my 0.02 cents worth.

72 dtg Kuwait
73 dtg Home

 

[STRIPES]

33 here with an easy hand and under 60. 25ish at 80+

 

[ksquared]

Guys: I appreciate all of the input so far, but I don't think I've made my concern clear. I never expected the R3T to get the same mileage as my Suzuki C90 or the Victory CrossRoads that I almost bought. The C90 had a 1462cc 60 HP engine; the CrossRoads has 106 ci with 92 HP, but also has a 6 speed tranny to help out with cruising MPG., along with a more frugal (i.e. less lossy) belt drive.

No - my concern is the DIFFERENCE between cruising at 60 - 70 MPH, where I see almost 40 MPG, and cruising at 70-80 MPH, where my mileage drops to the 20's. I can't understand what would cause that and I'm wondering if it's a service/warranty issue.

 

[GPMAZ]

Your mileage may improve a bit as it breaks in, but not much. My mileage results are similar. I can get over 40 MPG running below 65 and taking it real easy with the throttle. I can easily drop that to 30 with some extended periods of 80+ and having some fun with the throttle.

The good news is that is with D&Ds, trip K&Ns and Tuneboy. So an additional 40+ horsepower doesn't have to cost you terribly in the gas mileage department.