gas milage mods?


Gizmo

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None that I'm aware of. People have talked about eliminating the catalytic converter and have done so but no proof that it helps.
 

spamer80

Member
In theory removing the catalytic converter should make the mileage worth. In practic, no changes at all. And I'm really not sure why you want to improve it and if it's really possible. That's fuel injected bike. Until you try power commander or something similar which modify the mixture itself, I doubt you can do anything.
 

JimBob

New member
I was thinking of something like the power commander there are many similar ones. I'll see what i can find.
 


Knob

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So, here are some results. With Power Commander and also Autotune installed and also actively used. I'm riding all the time Autotune activated, letting it make corrections in +/- 20% frame.
Actually I was installing PC to get rid of this annoyng yank at about 80 kmh/3500rpm. But in the end got this kind of fuel consumption, seems good enough for me. Target AFR set for Autotune mostly 13.6/1.

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Gizmo

Member
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So, here are some results. With Power Commander and also Autotune installed and also actively used. I'm riding all the time Autotune activated, letting it make corrections in +/- 20% frame.
Actually I was installing PC to get rid of this annoyng yank at about 80 kmh/3500rpm. But in the end got this kind of fuel consumption, seems good enough for me. Target AFR set for Autotune mostly 13.6/1.

View attachment 676
After 166 'fill-ups,' I average 51.9 mpg (4,5321 L/100 km) with NO modifications to any of the onboard systems. (But till have the 'annoying yank' at 80 kmh/3500rpm, which I can live with!)
 
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Knob

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After 166 'fill-ups,' I average 51.9 mpg (4,5321 L/100 km) with NO modifications to another of the onboard systems. (But till have the 'annoying yank' at 80 kmh/3500rpm, which I can live with!)
Sure your consumption is realistic. And it depends somewhat on riding style ofcourse (mine is quite aggressive). And on weather temperature (it is not too warm in my riding area), engine temperature rarely goes over +70C/158F. Cooler running engine will consume some more fuel.
The smallest consumption 4,97L/100 km (=56.94mpg) I got riding two-up, smooth and non-agressive style...

BTW the end result about eliminating the "yank point" is the fuelmix is set considerably richer: about +20% @3500 rpm and 5% open throttle.

By setting Autotune to follow the AFR about 14,5/1 may give extraordinary numbers on fuel economy, but hey - who want to ride a motorcycle this way? :)
 
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Gizmo

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Sure your consumption is realistic. And it depends somewhat on riding style ofcourse (mine is quite aggressive). And on weather temperature (it is not too warm in my riding area), engine temperature rarely goes over +70C/158F. Cooler running engine will consume some more fuel.
The smallest consumption 4,97L/100 km (=56.94mpg) I got riding two-up, smooth and non-agressive style...

BTW the end result about eliminating the "yank point" is the fuelmix is set considerably richer: about +20% @3500 rpm and 5% open throttle.

By setting Autotune to follow the AFR about 14,5/1 may give extraordinary numbers on fuel economy, but hey - who want to ride a motorcycle this way? :)
Sorry I was mistaken, the 51.9 mpg was my LAST reading, I average 53.4 mpg with my 266 'fill-ups', my highest reading was 61.9 mpg, so far. AND since the Interstate is nearby, I am constantly running in the 80s with frequent runs at 100+, just to make sure that she is willing. AND your 4,97L/100 km only comes to 47.33 mpg. And isn't it true that colder temps causes more power and theoretically BETTER fuel consumption. Maybe here in The States, we are taught differently.
 

Knob

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Sorry I was mistaken, the 51.9 mpg was my LAST reading, I average 53.4 mpg with my 266 'fill-ups', my highest reading was 61.9 mpg, so far. AND since the Interstate is nearby, I am constantly running in the 80s with frequent runs at 100+, just to make sure that she is willing. AND your 4,97L/100 km only comes to 47.33 mpg. And isn't it true that colder temps causes more power and theoretically BETTER fuel consumption. Maybe here in The States, we are taught differently.
Yes, my mistake. Stupid me, living in a metric world, still confused about the mpg measuring unit. But I consider +/- 5L/100km still as a pretty good result (my 1500cc Goldwing was asking about 7...8L/100km). Maybe you have better quality fuels also in US available. In my life the lowest fuel consumption I had with Shell VPower, not available any more in my country.

Fuel and air should be measured by mass (not by volume). In colder weather the air is more dense, so its volume contains more oxygen. Therefore FI-system can insert more fuel. Therefore it is possible to get more power in cold weather. On the count of using more fuel ofcourse.
Also the lower octane gasoline will give lower consumption as it's mass/volume relation is a bit higher. A higher octane gas liter's mass is less than lower octane gas liter's mass. I was teached this way.
And there is also the reason in turbo engines they use intercoolers to get more air into engine, making possible to use more fuel same time.
 
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Gizmo

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My understanding is that purpose of the intercooler is to 'cool' the air before it comes in to the engine .... to give you BETTER combustion so why would you need to add additional fuel. 'In colder weather the air is more dense, so its volume contains more oxygen', if that is true 'more oxygen' would give you BETTER combustion therefore LESS need of fuel, don't you think!
 

Knob

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Site Suporter
My understanding is that purpose of the intercooler is to 'cool' the air before it comes in to the engine .... to give you BETTER combustion so why would you need to add additional fuel. 'In colder weather the air is more dense, so its volume contains more oxygen', if that is true 'more oxygen' would give you BETTER combustion therefore LESS need of fuel, don't you think!
Yes, right, intercooler is for making air cooler before it enters engine combustion chamber. And because the cool air is more dense, it contains more oxygen per weight per given air volume (kg/m3). And other gases too the air contains (mostly Nitrogen) ofcourse, but as those gases do not support burning, we usually will not speak much about them.

Therefore entering cooler air (=more air) into the engine there opens possibility to insert also more fuel and in the end get more power from the engine. The AFR should be close to optimal for this and power we are speaking is considered as maximum power.

Older motorcycles with carburetors even give you feeling having more power at colder morning weather than at warm summer midday. With FI this difference is not so strong as FI corrects itself automatically by oxygen sensor feedback.
But with modern FI it is easy to manage the AFR and therefore change engine settings for max power or maximum fuel efficiency. Even "iron out" those "yanks". Anyway in most cases there goes suggestion to set the AFR overall a bit richer than needed for optimal burning, for getting engine better cooled etc. AFR like 13.6/1 not 14.7/1.

BTW by my theory the "yank" in original fuel map is made for measuring emissions, both exhaust gases and noise. AFR made as lean as possible at certain point (engine starts "to sneeze" because of the lack of fuel), where environmentalists do their important measurements. Adding about 20% more fuel to this point (3500rpm @5% open throttle) on fuel map made the yank disappear.
Therefore while using the Power Commander we overrun the ECU and run the engine in sort of "emergency mode", eliminating the CPU's O2-sensor and making changes to fuel map by force.

In older bikes sometimes you can feel also that moment while carburetor switches over from pilot jet to main jet.
 

Gizmo

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Personally, I feel that Honda wouldn't have produce a product that had a 'problem' with the fuel mixture/mapping knowingly. They would have done extensive testing prior to making the DN01 available, OR had a recall to 'correct' said problem.
 

Knob

Member
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Personally, I feel that Honda wouldn't have produce a product that had a 'problem' with the fuel mixture/mapping knowingly. They would have done extensive testing prior to making the DN01 available, OR had a recall to 'correct' said problem.
Sure it would have been nice to meet a perfect motorcycle. Dealing with bikes over 40 years and never met such yet... But DN still is pretty close to my understandigs about perfect bike :)
Well balancing between riding and tinkering pleasures.
 

Gizmo

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Sure it would have been nice to meet a perfect motorcycle. Dealing with bikes over 40 years and never met such yet... But DN still is pretty close to my understandigs about perfect bike :)
Well balancing between riding and tinkering pleasures.
Just don't create TOO BIG of a can of worms 'tinkering!'
 

BobF

New member
I'd always thought that "yank" at 50mph was the transmission switching off and locking to direct drive when in automatic. I've never encountered it when riding in manual mode, even leaving in "6th" and crossing over 50mph.
 

Gizmo

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I'd always thought that "yank" at 50mph was the transmission switching off and locking to direct drive when in automatic. I've never encountered it when riding in manual mode, even leaving in "6th" and crossing over 50mph.
I agree with you but Knob and I had this discussion before and I just gave in! If he wants to 'tinker,' so be it.
 

Knob

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I'd always thought that "yank" at 50mph was the transmission switching off and locking to direct drive when in automatic. I've never encountered it when riding in manual mode, even leaving in "6th" and crossing over 50mph.
You do not notice the engine "sneezes" at the "yank", like engines do when fuel mix being too lean?
 

Gizmo

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SNEEZES? That's a new one! Knob, you definitely keep this forum 'interesting.' I do appreciate all time and effort/expertise you have put into the DN01 to make her better. She is a unique treasure. Thank you.
 

Knob

Member
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SNEEZES? That's a new one! Knob, you definitely keep this forum 'interesting.' I do appreciate all time and effort/expertise you have put into the DN01 to make her better. She is a unique treasure. Thank you.
How you, obviously speaking english as a native language, would describe the situation about engine, when fuel mixture is extremely lean? Backfiring perhaps..?
 


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