Gas Milage

[womanridge]

I'm riding a 2007 R-1200 RT. I left Milw. yesterday and crossed all of Wisconsin and Minn. Rode a total of 510 miles. All the gas I ran was 93 octane and my milage gauge indicated 52 mpg all day long. I my reset it each time I filled up.
Today, I rode accross S.D. and into Montana. I only found 91 octane all day and my MPG read around 40. Again I rode about 500 miles. Again I reset my MPG gauge each fill up.
Can someone explain this to me. I find it hard to believe such a difference just because of 93 vs. 91 octane. Didn't notice ethanol on any of the pumps. I have approx 14,500 miles on the bike. I just switched to synthetic oil last week, although I don't believe that is a factor.
Any ideas?

[dancogan]

Speeds and headwinds can make really significant differences. Were your speeds the same each day? Were you aided by a tailwind one day and fighting a headwind or crosswind the next?

[womanridge]

Good point, but I'm still baffled.
300 miles yesterday was 70+ on interstate, last 200 miles were 60+ with strong cross wind.
Today was 300 miles of cross winds at 65 mph, last 200 miles were no noticeable wind at 70+ mhp.

[DarkCloud]

It's not an octane thing. Nothing is wrong with your bike. If you stop at the same stations on the way back you should get about the same gas mileage.
When riding across the desserted midwest I try to fill in major cities so I get fresh gas. If the gas smells like varnish, it is stale, about a month old. JON

[MotorradMike]

I'm not familiar with your bike but if the manual says it requires 93 then performance will suffer if you can't get 93. You can get away with lower octane if you are gentle with the throttle but 70+MPH takes a fair amount of power even without headwind. 93 is a long way from 91 as well.

You have pretty much done the testing and you have the results. Put 93 back in and watch the mileage go back up.

I tried lower octane in my bike and got about the same results. Mine takes 90 which is half way between mid-grade and hi-test here in Ontario. I actually mix it half+half which is pretty anal and drives the cashiers nuts!

[zoridog]

These are two things that I have experienced when all other conditions are the same:

When using Plus or Premium you get "older" gas at those out of the way gas stations. If you need to stop at a remote station, get regular. Chances are it is fresh. Some of these remote places get Premium deliveries rarely. There might be a month of rainstorms in that Premium tank supply. Very bad for mileage. Buy higher octane gas at the highway stations. This season I have made gas station selection a priority and have not gotten a bad load of gas ... knock wood.

The other I experienced this weekend. We spent most of this morning riding in fog. The very high humidity requires more gas to burn the moist air. My buddy and I both lost about 4 mpg. The sun came out, we filled up, we got our mileage back.

[zoridog]

PS: I have gotten 1-2 mpg less since switching to synthetic oil about 1200 miles ago.

The only benefit synthetic I have experienced has been slightly less oil consumption and less smoke at start up. The engine does not run cooler or quieter. The RPMs have not increased as some claim. We shall see what the oil analysis says in May but I'm not a fan of the synthetics yet.

[AKBeemer]

Where I live the highest octane available is 90. I get 52-53 MPG on trips and 42-45 around town. Don't think the issue is the octane level of your fuel.

[podsobinski]

Another factor on the RT is how high you put your windshield. I have found that when I am alone and going highway or interstate speeds, I crank the windshield to the lowest setting and get 55 plus mpg. When I have the wife and windshield up almost all the way so we can communicate and keep buffeting down my mileage drops.

gpodzo

[womanridge]

Thanks all. After hearing all the input, I 'm leaning to "old gas". I was off the slab traveling on US 12 all day Monday. Lots of small towns. I had the windscreen down except for the last 200 miles yesterday during the rain.
I'll keep watching the guage and won't stress out over it.

[108625]

I live in Montana and just live with our gas all the time.
"High" octane is 91, mid-grade is 87, and "regular" is only 85.5. (Of course, prices aren't lowered accordingly, go figure). Our elevation and thinner air are the reason. You don't have to be in the mountains to be at 3,500+ feet. Many of us with MX or trail bikes which don't have self adjusting fuel injection or CV carbs drop the needle, change screw settings and/or jet them way leaner than we would to ride them closer to sea level.
Our Beemers run just fine on these octane levels, at these elevations.
(Yes, I'm aware that's at a reduced power output).
My R1200ST averages around 48-50 MPG.
My wife's old R1150RS routinely delivered 50-52 MPG.
Her new F800ST has really impressed us, getting well over 60 MPG on average.
Even our old airheads with Bing CV carbs average in the mid 40s.
The wind here can drastically affect your mileage, I've had it cut my old truck's range in half before.
Some service stations close at night (period, no automated pumps) so I would never advise passing one up in the country, thinking you'll find "fresher" fuel in the next town. The next town is often just another junction (intersection). There are often more grades of diesel available for the farmers than gas for motorists.
In addition, you can run into some methanol blended fuels to the east (way over there around Wyoming and the Dakotas).

Happy Trails!
Bob

[CJ3BNUT]

Your are also climbing in elevation across SD.

[cwsenn]

On my R1200RT the mileage has varied greatly on the same stretch of road from early morning to afternoon, raining versus sunny and elevation changes. I think it has more to do with the calmness of the day, moisture in the air, etc... I personally don't worry about it too much and just buy gas when I need it. It always does better than my cage's and lots more fun to drive. I of course enjoy the quick acceleration and am happy to pay more at the pump vice taking it easy on the acceleration and driving like my parents do there cage.

Chuck Senn

[wezul]

Recently I checked the mpg on my '07 RT after resetting the computer and running about 200 miles, 52.2. Not bad.
However, as previously posted, my '07 F800ST smokes that number.
I always run premium, seeking out BP or Shell. I found non-ethanol 93 octane in Waupun, WI. I like the idea of real gas as I understand ethanol is bad for rubber and plastic parts, you tech heads know the term (attracts moisture). I have not noticed a mileage difference though.

[SilverRT]

I agree with the posts regarding wind and elevation. I traveled west through the SD-ND-MT this summer and got 43MPG but averaged 52MPG on the total trip of 6,500 miles on my '07R1200RT. I've noticed the same in a car going west.

[konrad]

I agree with the posts regarding wind and elevation. I traveled west through the SD-ND-MT this summer and got 43MPG but averaged 52MPG on the total trip of 6,500 miles on my '07R1200RT. I've noticed the same in a car going west.

You stated that you checked your mileage via your "guage". Have you verified the actual mileage via actual miles travelled divided by actual measured fuel used? Just a thought.

[SilverRT]

Konrad,

Yes, the numbers were calculated using math, not the average reading on the gauge. I've fount that option to be comparable.