Fuel Mileage.

[John in PA]

Observation: I can get better fuel mileage riding two up, uphill and down on country and mountain roads for an hour or two (38-39 mpg) than I can running back and forth to work each way about 15 minutes one way (26-27 mpg).
I wonder if the temperature sensor isn't making good contact? I can't explain the poorer fuel mileage otherwise. Is it really needing to run that rich at cooler engine temp? My old carbeurated bikes run well without a choke after 2-3 miles, and get 52-57 mpg running on trips.

Do you ever get the feeling Progress ain't all it's cracked up to be?? (Don't get me started on "Hope and Change...")

 

[pbears]

How are you calculating your mpg John?. Are you using the trip computer and are your consumptions in US or Imperial gallons?
There are several other threads discussing this. My general rule of thumb, which has held through 6000 miles of mixed, but solo riding, is that I get 10 miles per litre, which translates to around 44 miles per imperial gallon and a run dry tank range of 180 miles (though infact I got 195 and 196 miles on the 2 occasions I actually ran it dry).
Cheers
Martin

 

[John in PA]

US gallons, using the trip computer. Trip computer seems to be about 10% pessimistic, but at least it's consistent, and it's about all you can use to check consumption on the fly. I might use trip2 to re-zero and check efficiencies at different points of a trip. The instantaneous fuel consumption on the Norge computer seems to have disappeared on the Stelvio one.

 

[kwn306]

John in PA wrote:

Observation: I can get better fuel mileage riding two up, uphill and down on country and mountain roads for an hour or two (38-39 mpg) than I can running back and forth to work each way about 15 minutes one way (26-27 mpg).
I wonder if the temperature sensor isn't making good contact? I can't explain the poorer fuel mileage otherwise. Is it really needing to run that rich at cooler engine temp? My old carbeurated bikes run well without a choke after 2-3 miles, and get 52-57 mpg running on trips.

Do you ever get the feeling Progress ain't all it's cracked up to be?? (Don't get me started on "Hope and Change...")

John,

My computer is way off in the mileage department, sometimes as far as 6 to 7 mpg. It doesn't make any difference if it is one up or two up, 30 to 80 mph.

What I do know is that my bike is now very cold natured in the morning since the first service was done. The bike just won’t take any throttle at all; it actually has cut out a few times. The bike has 2K in mileage, mostly all highway, 2 up my mileage varies between 31 - 36 mpg depending on the outside air temps, the warmer the better. I can't believe the mpg varies so much with the outside air temps, my 2003 Kawasaki Concours always gets 39 - 40 mpg, 2 up and that bike has 144,000 on the clock. The mpg has not changed a lick since new.

I like you think technology is bending us over :angry:

Kurt

 

[chipper]

Nearly 900 miles done on the stelvio and not impressed with fuel economy. I get about 120 miles on a full tank I can`t tell for sure if I am low so keep filling up when the fuel light comes on and the average fill up is £12.50. I hope after the 1st service things get better as everything else with the bike is great. Is this the norm. The computer says 33.9 mpg but I would expect at least 40 mpg for this type of bike is that guzzis are thirsty.Chipper

 

[Louis]

kwn306 wrote:

John in PA wrote:

Observation: I can get better fuel mileage riding two up, uphill and down on country and mountain roads for an hour or two (38-39 mpg) than I can running back and forth to work each way about 15 minutes one way (26-27 mpg).
I wonder if the temperature sensor isn't making good contact? I can't explain the poorer fuel mileage otherwise. Is it really needing to run that rich at cooler engine temp? My old carbeurated bikes run well without a choke after 2-3 miles, and get 52-57 mpg running on trips.

Do you ever get the feeling Progress ain't all it's cracked up to be?? (Don't get me started on "Hope and Change...")

John,

My computer is way off in the mileage department, sometimes as far as 6 to 7 mpg. It doesn't make any difference if it is one up or two up, 30 to 80 mph.

What I do know is that my bike is now very cold natured in the morning since the first service was done. The bike just won’t take any throttle at all; it actually has cut out a few times. The bike has 2K in mileage, mostly all highway, 2 up my mileage varies between 31 - 36 mpg depending on the outside air temps, the warmer the better. I can't believe the mpg varies so much with the outside air temps, my 2003 Kawasaki Concours always gets 39 - 40 mpg, 2 up and that bike has 144,000 on the clock. The mpg has not changed a lick since new.

I like you think technology is bending us over :angry:

Kurt

I also don't trust my tripcomputer, it always lies to me.
My Stelvio NTX with panniers, topcase and luggage on the backseat has now 2040 km's or 1268 miles.
My average fuelconsumption on mix of highway and countrie roads and a mix of touring- and sporty riding is.

42,38 mpg (Imp. Gallon)
35,29 mpg (US gallon)
1:15 (in Dutch)

Louis

 

[WayneOrwig]

I haven't check my trip computer closely, but a rough check showed it was reasonable.

I get 31-32 US MPG commuting.
I get 33-34 US MPG on a long country ride.

It sucks.

I leaned my fuel trim, but that makes zero difference once it is warmed up, and just makes it a bit cold blooded when you start it.

The 'instantanious' fuel economy usually runs close to 40 US MPG (actually, between 35 and 45, depending). But stop for a couple of red lights, and the over all economy drops like a rock.

I don't think you can blames the high tech part too much. I suspect it has a lot more to do with cylinder head design and spark advance, etc. The fuel and air is getting in and getting burned, so something isn't using it very efficiently.

Maybe this weekend I'll check the accuracy of the computer.

 

[Gary]

Chipper, the fuel computer is reading US gallons. If your putting in £12.50 then you got about 5 litres left in the tank when you fill it.
Divide the litres you put in by 4.5, that will come out at around 2.8 gallons, 120 miles / 2.8 gallons is around 42 mpg.

The black ones do much less because of the heavier paint.

 

[Penis Rotor]

The ETS on the 8V now sits at the base of the RH cylinder. I tried packing mine with thermal paste and unlike earlier bikes with the sensor in the head it seems to have made bugger-all difference. I can't honestly remember how accurate the temp reading was. I'm sure it's location and signal, along with the decay curve I imagine is in the map for cold start, is a contributing factor to the 8V, or some of thems', annoying reluctance to idle from cold consistently.

Yes, the fuel ecconomy is pretty lousy. I think at the end of the day it is simply down to crappy mapping. As you can see from the WFO fueling graph for mine it is ridiculously rich at the top end. Whether it is similarly rich on a lighter throttle I don't know yet. when i go to the Dyno again I'll try and get some more solid data recorded.

Pete

 

[RJVB]

Pete: how would you determine the accuracy of the temperature reading? Did you compare with a different, calibrated temperature sensor taking readings off the same spot?

I may be mistaken, but AFAIK the Euro-3 "rules" also contain fuel mileage criteria. If true, it's rather surprising to see arguments that the 4/8V motor is the future as the old two-valver cannot keep up with stricter regulations much longer, and yet see such an increase in consumption.

Do we know the situation with the 1200 Sport 8V?

 

[WayneOrwig]

I checked my computer today. My GPS showed a distance of 151 miles. The trip meter was exactly 151 also.
For that trip it showed 32.6 MPG. It took 4.16 gallons, for an actual fuel economy of 36.3.

So the dashboard computer is about 10% low.

 

[Penis Rotor]

RJVB wrote:

Pete: how would you determine the accuracy of the temperature reading? Did you compare with a different, calibrated temperature sensor taking readings off the same spot?


Do we know the situation with the 1200 Sport 8V?

By plugging in the axone which seems to accept the data from the ETS and interpret it with a reasonable degree of accuracy. Am I going to rig up some sort of remote fuel tank and then take a series of readings with some other tool? No what's the bloody point? there's sweet FA I could do about it anyway.

The reason why the engine is LESS fuel efficient at the moment is because a lot of the time it is running stupidly rich, especially at WFO and out of the closed loop portion of the map. This is simply down to crappy mapping I'm sure, you'll probably find that in the areas where the testing is done it's running very lean to satisfy the ecofascists but like most other vehicles, although to a greater degree, the map is rich elsewhere, especially at the top end to reduce power and save us from ourselves:S .

I'll bet a basket of bunyips that the 1200 Sportimunter will do exactly the same.

pete

 

[John in PA]

Speaking of fill-ups, have you found a trick for filling up that doesn't involve burping fuel all over the place out of the gas tank neck? I don't know what kind of wierdness they've stuck in for venting, but it's a pain to try to top off. And topping off sure would be nice since capacity is a bit lacking. I've been carrying a pair of 32oz MSR bottles strapped together in the topcase till I have a good feel for how far the reserve carries the beast.

I did cut a small nick in the gas cap seal to keep the tank from presurizing. Where's the valve you said you tinkered with to relieve pressure??

 

[BigRed]

I may only have about 500 miles on my beast, and my fuel mileage is aweful as well. However, I am thankful for the grin she puts on my face everytime were together .

Despite this, I would appreciate any advice to increase fuel mileage without sacrificing my right wrist?

 

[RJVB]

To get back to the ETS accuracy thing, the only assessment one gets from observing its output with the Axone is to what extent the shown values are acceptable, or representative of a known temperature working range of the engine.
The point in calibrating it? The same as with the ETS on the earlier engines, find out whether the ECU gets proper information about the engine temperature, or (possibly) not! The heat-conducting paste trick doesn't work, but that doesn't mean there's nothing else that could be done!

 

[Brian UK]

For what it's worth, I checked the accuracy of mine on the Norge by measuring the resistance at various temperatures, (using a digital probe thermometer to confirm temp), and compared the readings to the list given in the WS manual.
It was fine of course.

 

[WayneOrwig]

John in PA wrote:

I did cut a small nick in the gas cap seal to keep the tank from presurizing. Where's the valve you said you tinkered with to relieve pressure??

Avoid over filling it. I did that, burping the tank and all to get in just a little bit more. The engine heat expanded it and forced it past the seal UNDER the fuel cap (not where you can see it). It puddled up hidden on the plastic under the cap and stripped off all the paint around the fuel cap.

Luckily the bike was just one week old so they warrantied it.

Take off the cap and turn it over. There is a red plate under it. Remove that, being carefull of all the washers, valves and springs. I slightly damaged the seal under the ball, which is the tipover valve. You could also just totally remove the ball, if you wanted no tipover protection at all.

 

[WayneOrwig]

Brian UK wrote:

For what it's worth, I checked the accuracy of mine on the Norge by measuring the resistance at various temperatures, (using a digital probe thermometer to confirm temp), and compared the readings to the list given in the WS manual.
It was fine of course.

On past engine designs, the sensor worked fine, but they mounted it where it didn't pick up the actual engine temperature. It was either in a valve cover or in a plastic holder. In cool weather, it would report a cold engine even after a long ride and the ECU would still be running on 'chokes' (an over rich mixture).

 

[WayneOrwig]

One other thing to note.
I have been fiddling with many an older EV in the garage hooked to an O2 sniffer and the VDSTS software, and suddenly started seeing the mixture going richer and richer. I would of course have a fan on, but it wasn't enough. At some point it appears that the sensor would see an overly hot engine and the mixture richened a bit to help cool it.

Fix the sensor so it reads more heat, and you may make the fuel economy worse.

While out yesterday, I was getting about 32 MPG. When I stopped for fuel and reset the trip meter, I was then getting a bit over 40 MPG. But about 10 miles later I came to a small town with a couple of traffic stops, bam, down to 34 MPG and NO going back up.

I'm starting to think they go rich at low speeds to cool the motor a little.

 

[Smoothy]

Just covered 120 miles today on 1 tank averaging 40MPG although I am restricted due to running in.

Didn't seem any worse than my R1100S