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normal operating temp and mpg?


jeffro7172

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my bike regularly sees 210-219 on my work commute and it's 40-50 degrees out. I believe it was in the 220's when I was commuting around LA when I bought it (warmer out) I haven't had it long enough to see what it runs in real heat, but also want to make sure it's not close to overheating either.

Haven't gone through and changed all the fluids yet, but just wondered what you all are seeing on your bikes....2001 FI model by the way.

what is "overheating" temp?

see mpg ?? below

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thanks John....puts my mind at ease...what kind of MPG do you get? this last tank I tried to keep from punching it and I got 134 miles out of the tank and crammed 4.8 into it....28 mpg. It's a backroad commute stop and go with a couple stretches of 70 in it. 17 miles each way....just wondering....I know it's probably not the most economical mileage wise but figured mid 30's would be the norm..

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..what kind of MPG do you get? this last tank I tried to keep from punching it and I got 134 miles out of the tank and crammed 4.8 into it....28 mpg. It's a backroad commute stop and go with a couple stretches of 70 in it. 17 miles each way....just wondering....I know it's probably not the most economical mileage wise but figured mid 30's would be the norm..

Is your bike parked in the sun all day at work ?

That might account for the low mileage number.

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I got an 02' and I get alittle over 40mpg being a good little boy and not taking off to hard and keeping it under 70. I normally get high 20's if I am in the mountains playing for extended legnths of time and hardly go under 6k rpm's much..

What all you got done to your bike? How many miles?

might wanna look at your air filter, spark plugs, if you got a PC on your bike might want to disconnect it for a few trips and see if anything changes, or maybe reload your map thats suppose to be in it. Maybe run some seafoam through a couple of tanks. Doubt you need it, but have you ever had the valves checked? Are your brakes dragging any? Just a few things to look at.

Gotta watch critters if you bike sits for a legnth of time, they enjoy making nests. On my old 750 yrs ago I made a list on a notepad for things to do and check for my bike over the winter. Some how the list went missing. I found it a week later while checking my K&N filter. All ripped up and colored red from the oil on the filter. Had me stumped what it was for a second till I saw my writting on a few pieces.

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thanks Krypt Keeper....I will go through and give it a tuneup (which I was planning on anyway) sounds like it'll run even better after that's all done. Bike is stock and prior maint is word of mouth only. It's got 17k miles on it. 40mpg "being a good boy" is a far cry from the 28 I just did on this tank trying to "be a good boy".....

thanks for the replies everyone!

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Pull the vacuum line off of the fuel pressure regulator(FPR) and check for any fuel. If there is any at all, the regulator needs to be replaced. Bad MPG is an early sign that FPR is going.

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MPG in real city riding sucks when it is cold.In my commute I have a problem getting 30 mpg when temps drop into 30-40 deg range.

On the other hand bike gets mid to upper 40s when cheating .( higher elevation,like,cough,Colorado in the summer).

Actually, I was thinking about it,Ram Air does not help in this area,fuel mixed with cold air has a problem vaporizing.The other thing is oil cooler,XX has actual cooler unlike most of the bikes that are equipped with coolant/oil heat exchanger .Oil system on XX does not have thermostat,it is safe to assume lubricant does not reach optimum temperature when is cold.That increases parasitic losses.

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MPG in real city riding sucks when it is cold.In my commute I have a problem getting 30 mpg when temps drop into 30-40 deg range.

On the other hand bike gets mid to upper 40s when cheating .( higher elevation,like,cough,Colorado in the summer).

Actually, I was thinking about it,Ram Air does not help in this area,fuel mixed with cold air has a problem vaporizing.The other thing is oil cooler,XX has actual cooler unlike most of the bikes that are equipped with coolant/oil heat exchanger .Oil system on XX does not have thermostat,it is safe to assume lubricant does not reach optimum temperature when is cold.That increases parasitic losses.

:icon_lol:

Yep that's it, just move to Colorado and you'll magically get better gas mileage. :icon_duh:

...

Now as for the second part.... BAM ! ... Right on the Money. Good Point.

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Yep that's it, just move to Colorado and you'll magically get better gas mileage. :icon_duh:

All my bikes get better MPG in Colorado. I can't explain it. Even with F/I.

So less air would make the bike get less fuel, but then you just twist the throttle a bit more so you should be back where you started.

But it doesn't work that way. Less moisture in the air?

My H/D gets 50 mpg when in Co.

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It's simple the higher up you are the less Oxygen in the air, the bike puts less fuel in because there is less Oxygen. Gives you better MPG but less HP. For example on a dyno at sea level your XX makes 130HP. If you dyno your bike at 5000 feet you'd get about 20HP less. Most dyno's correct the HP reading to sea level BUT doesn't change that your bike made 20 less HP. Since you make less HP you need less fuel to make it.

My XX was getting between 30-35MPG highway before I had it dyno tuned. After the custom map I was getting 40-45MPG at 140Km/h (85MPH). Keep in mind this is just at cruising speed and all highway(and +1T on the front sprocket).

Before the tune on the highway 310Km was my MAX on a tank(digital dash and gas light flashed for at least 50-60Km) and when I pulled in for gas it was on fumes. After the tune the same 310Km stretch(no other changes) I still had more than 1/4 tank showing on the gauge. Both trips were made with full Givi luggage and the same gear/supplies on the bike.

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MPG in real city riding sucks when it is cold.In my commute I have a problem getting 30 mpg when temps drop into 30-40 deg range.

On the other hand bike gets mid to upper 40s when cheating .( higher elevation,like,cough,Colorado in the summer).

Actually, I was thinking about it,Ram Air does not help in this area,fuel mixed with cold air has a problem vaporizing.The other thing is oil cooler,XX has actual cooler unlike most of the bikes that are equipped with coolant/oil heat exchanger .Oil system on XX does not have thermostat,it is safe to assume lubricant does not reach optimum temperature when is cold.That increases parasitic losses.

:icon_lol:

Yep that's it, just move to Colorado and you'll magically get better gas mileage. :icon_duh:

...

Yes,you do .The air is simply thinner,less aero drag.Motorcycles have,relatively speaking,barn door`s aerodynamics,that is way MPG improvement is really noticeable,about 15-20% in my case.

Even in the car I would typically get 10% MPG improvement in mile high states like Colo,or Wyoming.

If look at performance date for the airplanes with turbocharged piston engines that can maintain absolute manifold pressure( and consequently hp) to really high elevation like WW2`s P47 or P38 you would notice that their top speed at,let`s 25000 feet, is about 80-100 mph higher then at sea level.360-370 vs.440-460mph.

Same with fuel consumption,planes burn more fuel at lower elevations.

That is why comparing MPGs without mentioning elevation is not really accurate,or cheating. :icon_twisted:

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my bike regularly sees 210-219 on my work commute and it's 40-50 degrees out. I believe it was in the 220's when I was commuting around LA when I bought it (warmer out) I haven't had it long enough to see what it runs in real heat, but also want to make sure it's not close to overheating either.

Haven't gone through and changed all the fluids yet, but just wondered what you all are seeing on your bikes....2001 FI model by the way.

what is "overheating" temp?

see mpg ?? below

I would try Engine Ice or Redline Water Wetter and water to keep the engine running cooler as long as the temp does not go below freezing (add antifreeze as needed). Your temp while moving will come down to 180-185. My thermostat opens at about 182. At start up I'll see the temp build to 182 and drop a few times as the cold mix in the radiator gets into the engine the first few times. I run 50/50 plus 1/2 bottle of Water Wetter. At speeds over 50mph when the temp is around 50F my temp will stay in the 180-185 range. In traffic, at 222 or so the fans comes on and it shuts off at 210. I try and keep moving and normally my fans do not come on.

PS: I good thing about synthetic oil is the viscosity stays more consistent over a wider temperature range.

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It's simple the higher up you are the less Oxygen in the air, the bike puts less fuel in because there is less Oxygen. Gives you better MPG but less HP. For example on a dyno at sea level your XX makes 130HP. If you dyno your bike at 5000 feet you'd get about 20HP less. Most dyno's correct the HP reading to sea level BUT doesn't change that your bike made 20 less HP. Since you make less HP you need less fuel to make it.

But..............

Let's say at sea level it takes 30 hp. to maintain 60 mph level.

So now you go to 10,000' you make less hp. Right? So you can't maintain 60 mph. (at a given throttle setting)

The answer is to twist the throttle to add more fuel/air to get back to 30 hp. & 60 mph.

So shouldn't you get the same mileage as at sea level?

I'm missing something. And I think it's the density of the air, not the volume.

I actually think the bike F/I, runs better at altitude, sounds smoother, happier.

I know it's nuts.

As far as temp. My fan doesn't even kick on until 219 F.

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my bike regularly sees 210-219 on my work commute and it's 40-50 degrees out. I believe it was in the 220's when I was commuting around LA when I bought it

Also remember that the bird doesn't pump enough water to cool the engine if you are below 4000 rpm. At stoplights, the temp soars. Kick it up to 4 K in traffic and it helps.

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Manifold Absolute pressure sensor, map sensor, gauges the airbox pressure, and sets the amount of time the injectors are open. Air fuel ratios are the same, air densities the bike passes through are different. Thick air resist the bike more than thin air. Bikes are bricks compaired to other vehicles. Drag coefficient higher.

Unless engine temp is 212 condensate will accumulate in the oil and reduce lubricity of the oil and drag internal parts, hence wear and higher parasitic losses.

Fuel contacting the cylinder at lower temps condensates to a liquid and will not mix with air or burn quickly, leaning the mixture and diluting the oil film on the walls causing the rings to contact metal to metal and wearing both. More parasitic drag.

That is why engine temps are like they are. Even higher are even better. Until oil breakdown, higher is better. Check out Smokey Yunicky's exhaust heated engine intakes that make 300 hp from twin cylinder engines.

http://smokeyyunick.com/

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Less moisture in the air?

Correct. Now your getting closer to the answer.

I know the 2000 has a barometer sensor, but the 2002 does not. so. M.a.p. is the only way it can adjust fuel quantity.

Correct..... but the bike does NOT have Closed Loop Oxygen sensor, nor an intake air Temperature sensor.

So our bikes adjust for Oxygen content based on a Map that's programmed into the ECU. Basically there's a map that says when the pressure is X the oxygen level is Y, then the FI system delivers the proper amount of fuel based on your TP, and RPM signals.

Yes,you do .The air is simply thinner,less aero drag.Motorcycles have,relatively speaking,barn door`s aerodynamics,that is way MPG improvement is really noticeable,about 15-20% in my case.

Even in the car I would typically get 10% MPG improvement in mile high states like Colo,or Wyoming.

If look at performance date for the airplanes with turbocharged piston engines that can maintain absolute manifold pressure( and consequently hp) to really high elevation like WW2`s P47 or P38 you would notice that their top speed at,let`s 25000 feet, is about 80-100 mph higher then at sea level.360-370 vs.440-460mph.

Same with fuel consumption,planes burn more fuel at lower elevations.

That is why comparing MPGs without mentioning elevation is not really accurate,or cheating. :icon_twisted:

First part... partially correct, I say partially because the Aero drag dose not account for all of the improved Mileage.

If that was the Case then the Older Carburetor motorcycles would have gotten better gas mileage at altitude as well... and that didn't happen, in fact they often used a lot more fuel. But then we're talking about venturies and flow velocities, and ... well lets just not go there.

....

The answer to all of the above is the relativity of Specific Fuel content, to Oxygen, to Humidity, to Barometric pressure, to Temperature, to Flow Velocity, to rolling resistance, to aerodynamic drag.

Just as a reference, there's 4% more oxygen at 50 degrees than there is at 70 degrees.

It's a big soup bowl... and all of the ingredients account for the power of the soup.

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Less moisture in the air?

Correct. Now your getting closer to the answer.

I know the 2000 has a barometer sensor, but the 2002 does not. so. M.a.p. is the only way it can adjust fuel quantity.

Correct..... but the bike does NOT have Closed Loop Oxygen sensor, nor an intake air Temperature sensor.

So our bikes adjust for Oxygen content based on a Map that's programmed into the ECU. Basically there's a map that says when the pressure is X the oxygen level is Y, then the FI system delivers the proper amount of fuel based on your TP, and RPM signals.

Yes,you do .The air is simply thinner,less aero drag.Motorcycles have,relatively speaking,barn door`s aerodynamics,that is way MPG improvement is really noticeable,about 15-20% in my case.

Even in the car I would typically get 10% MPG improvement in mile high states like Colo,or Wyoming.

If look at performance date for the airplanes with turbocharged piston engines that can maintain absolute manifold pressure( and consequently hp) to really high elevation like WW2`s P47 or P38 you would notice that their top speed at,let`s 25000 feet, is about 80-100 mph higher then at sea level.360-370 vs.440-460mph.

Same with fuel consumption,planes burn more fuel at lower elevations.

That is why comparing MPGs without mentioning elevation is not really accurate,or cheating. :icon_twisted:

First part... partially correct, I say partially because the Aero drag dose not account for all of the improved Mileage.

If that was the Case then the Older Carburetor motorcycles would have gotten better gas mileage at altitude as well... and that didn't happen, in fact they often used a lot more fuel. But then we're talking about venturies and flow velocities, and ... well lets just not go there.

Well,typical CV motorcycle carb cannot maintain proper A/F ratio,mixture gets rich at elevation,so decreased aero drag is offset by improper for given elevation carb setting.Properly working FI system does not have this problem.

....

The answer to all of the above is the relativity of Specific Fuel content, to Oxygen, to Humidity, to Barometric pressure, to Temperature, to Flow Velocity, to rolling resistance, to aerodynamic drag.

Just as a reference, there's 4% more oxygen at 50 degrees than there is at 70 degrees.

What that has to do with the above discussion ?,specific weight of gas for given pressure depends on the temperature,it is straight relation to absolute zero or -273 C,50F is about 10C,70Fis about21 C so 294/283=1.039,so yea,it is 4%

The bottom line is,if car/bike/truck/airplane can maintain proper A/F ratio MPG improves with elevation gain.

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It does have a IAT.

Good to know, but adds a monkey to the math problem...... danggit!

The bottom line is,if a car/bike/truck/airplane can maintain proper A/F ratio, MPG improves with elevation gain.

IF is a really big word... and in this instance, speaking about the CBR1100XX... it proves to be bigger than it sounds.

Which is my point.... the Bird CANNOT maintain the proper A/F ratio across the elevation gain/loss scale accurately.

Because of this, the mileage gain that one can see if he or she rides there FI Bird up at elevation, is not due to Aerodynamic gains, it's due to a ECU and Sensors that are not programmed, or cannot, measure enough supporting data accurately enough, to keep the AFR's the same, at all elevations.

At 3000 feet I have recorded 13:1 afr's @ a given Speed, RPM, & TP. At 6000 feet elevation, under about the same conditions my Datta Logger will record 13.5:1 afr's.

Now I know what you're thinking... less Load on the bike at elevation means less need for fuel, and hence the higher AFR's, but... once again if you record enough data on a Datta Logger on the Bird, then you'll soon see that every time the Load in decreased,(ie: going downhill, going with the wind, etc.), the Bird runs Richer.

And under a very slightly increased load, the AFR's will Lean out, (ie: pull a very slight hill, or go into a headwind, etc.). But it has to be only a very slight increase in load, or else the AFR's once again will drop like a stone, and get really Rich, really fast.

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It does have a IAT.

Good to know, but adds a monkey to the math problem...... danggit!

The bottom line is,if a car/bike/truck/airplane can maintain proper A/F ratio, MPG improves with elevation gain.

At 3000 feet I have recorded 13:1 afr's @ a given Speed, RPM, & TP. At 6000 feet elevation, under about the same conditions my Datta Logger will record 13.5:1 afr's.

Can you get exactly the same TP for given speed at 3000 and 6000 Ft ? Just curious,honestly I`m,I`d say you gotta give more throttle,sure aero drag is decreased as much as power but rolling resistance stays the same,so,,,,,,,,,,more throttle ?

All the mileage discussion aside,I`ve never bother to hook up my wideband to XX but my butt confirms your observation,XX does lean out with elevation to some degree.Every time I get to the high mountains I have to give more fuel via buttons on Power Commander or bike is almost unridable .My Chicago`s,600ft, map suddenly becomes too lean for those conditions.Contrary,my FI R1 goes the other way,becomes really rich on 10000-11000 ft passes.Go figure,well, in real engines simple arithmetic calculations regarding air density via BARO,or MAP don`t work very well,engines should really be mapped at elevation.Theoretically,at 10000 ft you would give 30% less fuel and call it a day,but that does not really work that way.

Of course ,change from 13.0 to 13.5 A/F fails to explain 15-20% MPG jump.Just like I said it is due to less aero drag. :icon_twisted:

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