Which dynojet for '04 V11?

[Guest Phil_P]

If Power Commanders didn't do the job they are supposed to, ie, getting the fuelling something like stoichometric, then all the custom maps that folks have had produced by running their bikes on the dynamometer with tuning link software would have come back with a load of zero's in the matrix. Now isn't it strange that they don't? Or are you going to suggest that these techs have such a vested interest in making the PC's look good that they deliberately mistune the bikes they work on?

 

What a complete load of tosh. Guzzi's by the score have been released to the market with extremely sub-optimal fueling (for whatever reason). If you believe otherwise, then I am happy for you. My experiences and those of countless others suggest otherwise.

[Guest ratchethack]

Well said, Phil. I've met and rode with lots o' V11 Guzzisti over my 5 year ownership of my own Guzzi. Of all of them (myself included), I can't recall more than a few who aren't running a PC III. I'd be surprised if any less than half the posters to this forum who own V11's aren't using them, and of these, there may be a very few who don't consider it one of the best things they've done to their V11 -- but not many. Count me among the overwhelming majority of very happy customers.

 

Has there ever been a successful product of any kind that provides great value to a great number of customers that DOESN'T get an unsupportble bad rap from a few stray nut logs who want to wave their resumes -- whilst flinging accusations toward others as "egocentric", yet!! -- but who possess ZERO experience with them, and who get a bug up their butt (over who knows what?) and feel the need to broadcast unqualified, false information?

[jimbemotumbo]

Have to agree with the PCIII ... owners know.

Of course, I will always recommend a new Guzzisti perform a careful tune.

Most find that a good valve adjustment, and careful TB / EFI set up make them quite happy.

Some of these happy folk may surmise the PCIII is therefore a waste of good beer money.

Although a very happy camper post tune, the addition of the PCIII made me downright giddy.

Yeah, it took some fiddling to get it right, but well worth the effort. My best maps had few zeros, FWIW.

[Ryland3210]

Kevin H, hat's off to you as well for your efforts on behalf of Guzzidom.

 

There's always a danger of misunderstanding in purely written communication. I think some of that occurred here, but enough said.

 

Some good things came out of this, from my perspective. I'm sure many appreciated reading the background experiences of those who shared that. I certainly did.

 

There is one thing I would like cleared up by yourself or anyone else that knows the specifics. I recall reading about a "flag" in the mapping which was described as the ECU interpreting everything below a particilar TPS voltage as "idling". I'm not exactly sure what that means. One possibility is that the amount of fuel delivered per cylinder pulse is the same regardless of TPS voltage below that "idling" TPS voltage threshhold. If that is the case, it seems to me that at a constant RPM, because the amount of air delivered (i.e. vacuum) is the same whether the throttle plates are open more and the bypasses less, or the reverse, the mixture would not change. It also indicates that if one adjusts for a lower RPM, mixture might change, depending on whether the fuel mapping reflects simply the amount of fuel per pulse, or is also a function of RPM. Do you or anyone reading this know which it is?

[Guest Phil_P]

Kevin, you may not reply, so be it. However I still feel the need to challenge some of your statements.

 

1) Bikes with PC's make no more power than with a standard ECU.

 

You have some evidence to back this up I assume? I on the other hand concede that perhaps not all bikes with PC's will see an overall increase in power, however many will experience large improvements especially in the midrange where no amount of bypass screw and idle mixture fiddling will have any effect.

 

2) It's an unnecessary, aftermarket added complexity and a gimmick.

 

Yes, there is a degree of complexity added, however some method of tuning is most certainly required on many bikes. Your preference is to tune stock ECU's mine is to use a PC. As such, what makes it a gimmick? Your outlay may be less than mine, I am happy to spend what I have. I have also spent on a Creedon chip to gain the benefits THAT provides in firmware for altitude compensation and the dreaded idle/die that many Sportis' suffer from. Will's own advice is that an optimum tune will probably be obtained with a combination of his chip AND the PC.

 

3) In fact, most of these are typically a result of improper/sloppy tuning, or improper valve clearance.

 

Sorry, doesn't wash. I could set my valves a dozen times and tweek the TPS all I like, it still wouldn't fill out the hole in my midrange, and I suspect many others. Again, do you have any empirical evidence to back up this claim?

 

4) We're just trained to think that "stock is bad"

 

Surely if you are doing all the fiddling that you claim to be, stock IS bad?

 

 

Although an attack on PC's is, as you say, not a personal attack, your criticisms do sound personal when you make it sound like those who use them are being duped and deceived, and are foolish to do so. I personally think that YOUR solution of mapping and tuning software is an elegant and effective solution, and is perfectly valid as an alternative to using the PC (as are Cliffs' MY units). Personally I like the PC solution, I like the user interface and the ability to tune a little wherever I am with 'on unit' controls. I like the facilities provided by the add on LCD display although I haven't got one of those yet. I like the idea of being able to use the PC as the control system behind a quick shift outfit. I have even thought about fitting nitrous to the bike, for which the PC provides a perfect enrichment system.I also like the fact that (unlike Dyna ignition) in the event of failure you just take it out of circuit and resort to stock, although were I forced to do so, I know from experimentation that my bike would run like a bag of spanners.

 

As you imply in your posting, to each their own. I bet you will find by being marginally less overtly critical of my (and many others) chosen solution, people remain much more laisez faire and less likely to jump down your throat.

[Ryland3210]

I'm not sure I completely understand what you're getting at, but here goes:

 

The bypass screws, in my experience, mildly affect the off-idle response up to approximately 2,000 RPM. The volume of fuel injected has to increase as RPM increases, otherwise the engine would stall. But the mixture does seem to be static, or at least somewhat influenced by idle trim and bypass screws. So I guess that would be the "flag" value you refer to. Now that corresponding TPS value depends upon the baseline TPS setting. My readings are always in degrees, since I use the VDSTS (Vehicle Diagnostic Scan Tool Software). I would have to hook the bike up to the computer, run it to 2K RPM and observe the TPS value. I have no idea what that is offhand. There's probably a chart somewhere that provides the resistance values (converts to mV) at TPS openings. The factory EFI supplements perhaps.

 

I don't know what you mean by "adjust for a lower RPM"? You mean at idle? If the throttle plates are opened or closed slightly from a static position with the stop screws, the idle mixture will change. If the bypass screws are turned slightly, I believe the mixture also changes, but to a much lesser degree.

 

I also firmly believe that adjusting the TPS within the acceptable range of values also changes the mixture, as the ECU "thinks" the throttle plates are in a different position. Depending on RPM, fuel input and/or timing advance may change, but both will ultimately alter the burn mixture. For example: I recently reset my TPS to a higher value after developing a mild hiccup/misfire around 4K RPM. Somehow, after 2-3 years it had backed off 0.6 degree. I reset it to 3.7 degrees (with VDSTS software) and COULD NOT BELIEVE THE DIFFERENCE IN SMOOTHNESS AND OUTPUT. Since I always run 4K on the highway, this had become a REAL DRAG. It had developed so gradually that I did not notice it until there was a definitive problem. Now all is good in my Guzzi world again.

 

So, that's probably something of an answer. If you want to get into injector timing and pulse widths someone else will need to take that up.

 

Thanks. Actually I was dealing strickly in the idle regime. By "adjust for lower RPM", I meant the difference between adjusting the bypass screws to achieve, say 1200 RPM, at 3.7 degrees, versus, 1000 RPM. With 3.7 degrees in both cases, the lower RPM would require lower air bypass. Now if the fuel delivery is the same for all degrees below the amount "flagged" by the ECU software, would the mixture therefore be richer at the lower RPM. That's what I was trying to confirm.

[dlaing]

Thanks. Actually I was dealing strickly in the idle regime. By "adjust for lower RPM", I meant the difference between adjusting the bypass screws to achieve, say 1200 RPM, at 3.7 degrees, versus, 1000 RPM. With 3.7 degrees in both cases, the lower RPM would require lower air bypass. Now if the fuel delivery is the same for all degrees below the amount "flagged" by the ECU software, would the mixture therefore be richer at the lower RPM. That's what I was trying to confirm.

I think the idle flag is an urban legend

I am positive that the scenario you portray would result in a richer mixture.

And so would lowering the butterflies to get 1000 RPM and then adjusting the TPS back to 3.7 degrees.

What perplexes me is how the engine would run comparatively between the two 1000 RPM/ 3.7 degree scenarios.

I don't like the idea of messing with such unknowns.

It makes sense to me to start with factory tuning specs and then adjust the map as needed.

Yes one can tweak with TPS and air screws, but results across the map are not always what one might predict.

In general a higher TPS number makes the bike run richer, but timing also changes, and if the TPS number is too high, the resulting mapped cells overlap designed map cells, which in some places in the map can cause problems.

I don't know exactly what the "trim" control does in the VDSTS software. Although it is a weak substitute for re-mapping, to me it would make more sense to adjust trim rather than put the TPS off-spec to make the bike run rich enough. just my two cents...

[Cliff]

I could add an idle flag but it wouldn't do much.

[Ryland3210]

I think the idle flag is an urban legend

I am positive that the scenario you portray would result in a richer mixture.

And so would lowering the butterflies to get 1000 RPM and then adjusting the TPS back to 3.7 degrees.

What perplexes me is how the engine would run comparatively between the two 1000 RPM/ 3.7 degree scenarios.

I don't like the idea of messing with such unknowns.

It makes sense to me to start with factory tuning specs and then adjust the map as needed.

Yes one can tweak with TPS and air screws, but results across the map are not always what one might predict.

In general a higher TPS number makes the bike run richer, but timing also changes, and if the TPS number is too high, the resulting mapped cells overlap designed map cells, which in some places in the map can cause problems.

I don't know exactly what the "trim" control does in the VDSTS software. Although it is a weak substitute for re-mapping, to me it would make more sense to adjust trim rather than put the TPS off-spec to make the bike run rich enough. just my two cents...

 

I don't think it's worth pursuing if its an urban legend. I was just curious, with no problem that needed solving.

[Ryland3210]

I could add an idle flag but it wouldn't do much.

 

Personally, I wouldn't bother. It doesn't seem there is any need.

[Guest drknow]

The utility of a product, or a business for that matter, is in the service they provide to you. Kevin is welcome to eschew a Power Commander. They are not a necessary product, unlike tires or gas. However, they are a valuable product that provides a great and useful service for many people. Witness the AMA paddock, 90 + % of those bikes have them; the rest have an alternate form of mapping adjustment. Racers use them because they provide value, add better fueling capabilities, which translates into better laptimes. Street guys use them for the same basic reason, better horsepower/throttle response. Arguing they have no utility is like arguing against the value of grips. You COULD ride without them, but why?! If these bikes had carbs still, it would be like arguing against ever changing a jet--it's the same thing!

 

RacerX has provided a great service to the folks in the Guzzi community. Other than Kevin's comments, I can't think of anyone who doesn't respect him, or value the products he endorses or sells. Internet businesses are everywhere, there are less and less brick and mortar establishments available for niche markets. If someone prefers to buy their power commander from their local dealer, good for them. I think that's a good idea when possible. For MANY in the guzzi community, that's not a realistic proposition.

 

To sum up:

 

Guzzitech + PCIII =

 

dk

[Ryland3210]

Yes, and I realize it's kind of screwy, but ultimately altering the mixture at idle is the only way to adjust the idle speed. Whether it's done with the throttle stop screws, bypass screws, or TPS, the end result is the same. This is because there is no ECU "adjustment" at idle like an auto. It's a primitive system. Some newer machines have a "fully compensated" running scheme, like Kawasaki and probably BMW. I don't know about the latest Guzzis.

 

I suppose in a perfect scenario you would have the mixture adjusted perfectly at the throttle butterfly opening, and this is achieved with an EGA (exhaust gas analyser). Otherwise, the mixture is just leaned or richened to raise or lower the idle speed. That's not an ideal situation.

 

I still have my doubts, and appreciate your patience.

 

Let's look at two variables: The amount of fuel delivered per pulse, and the amount of fuel per pulse as it varies with degrees.

 

Case one: the amount of fuel per pulse below a certain "flagged" degrees open is always the same, no matter what the throttle opening is. Then Fuel delivered per minute is proportional to RPM, so as air bypass is increased the amounts of air and fuel are both increased proportional to RPM, and the ratio of fuel to air stays constant. It is always the same ratio, so long at the throttle degrees stay below the "flagged" amount, even if the degrees open changes.

 

Case two: the amount of fuel per pulse is a function of degrees open for all degrees open. Then fuel delivered per minute is proportional to RPM, but depends also on TPS voltage as well. So for a given TPS voltage, the fuel are ratio stays the same as RPM increases when the air bypass is increased, but the fuel air ratio can be changed by adjusting the degrees open.

 

Which one is it? Or is there a third possibility? Keeping in mind, I'm only asking about the idle regime.

[Ryland3210]

The first seems more likely, except that when I adjust the bypass screws to a different setting the engine behaves differently off idle up to 2K RPM. That would indicate that the bypass screws are affecting the mixture, which is all that they could do, as they regulate air. The bypass screws seem to have a greater affect on idle speed than TPS setting. I think that the baseline TPS setting puts the ECU at a certain point on the "graph" of the map, then the ECU modifies this as it receives input from the sensors, above the "flag" value.

 

If case 1 is correct, then mixture ratio would only stay constant below the flagged degrees. Above that point, it would affect ratio and account for the change in behavior you see.

 

For example, suppose in case 1A, we use more airbypass with a lower throttle opening, and in case 1B, we do the opposite. In both cases, we adjust for 1150 RPM. The mixture ratio is the same in both cases below the flagged degrees. However, above the flagged degrees, the fuel delivery mapping is a function of TPS voltage, so 1A would run leaner than 1B. As throttle opening increases, at some poiint, the air bypass becomes insignificant compared to the total volume of air flowing. That is probably the reason why you would see a difference up to 2,000 RPM. It also means that off idle and above mixture can be adjusted by modifying the TPS at idle (as long as you stay below the flagged level, while still maintaining the factory calibration on idle mixture.

 

Does that make sense?

[dlaing]

I still have my doubts, and appreciate your patience.

 

Let's look at two variables: The amount of fuel delivered per pulse, and the amount of fuel per pulse as it varies with degrees.

 

Case one: the amount of fuel per pulse below a certain "flagged" degrees open is always the same, no matter what the throttle opening is. Then Fuel delivered per minute is proportional to RPM, so as air bypass is increased the amounts of air and fuel are both increased proportional to RPM, and the ratio of fuel to air stays constant. It is always the same ratio, so long at the throttle degrees stay below the "flagged" amount, even if the degrees open changes.

 

Case two: the amount of fuel per pulse is a function of degrees open for all degrees open. Then fuel delivered per minute is proportional to RPM, but depends also on TPS voltage as well. So for a given TPS voltage, the fuel are ratio stays the same as RPM increases when the air bypass is increased, but the fuel air ratio can be changed by adjusting the degrees open.

 

Which one is it? Or is there a third possibility? Keeping in mind, I'm only asking about the idle regime.

My money is on case two.

My Tuneboy software shows fuel and ignition cells with numerical entries of fuel pulse time, based on throttle opening and RPM.

I believe it obeys the cells and not a flag.

Tuneboy does not show an idle flag.

Perhaps the VDSTS or Axeone software recognize an idle flag???????

It could be that the trim modifies only the fueling under the flag???????

What else would the flag be used for??? Simply a notation???? maybe like a graffiti tag???

[Ryland3210]

My money is on case two.

My Tuneboy software shows fuel and ignition cells with numerical entries of fuel pulse time, based on throttle opening and RPM.

I believe it obeys the cells and not a flag.

Tuneboy does not show an idle flag.

Perhaps the VDSTS or Axeone software recognize an idle flag???????

It could be that the trim modifies only the fueling under the flag???????

What else would the flag be used for??? Simply a notation???? maybe like a graffiti tag???

 

How low do the cells go in your Tuneboy? In other words, how low in degrees/TPS voltage does your map go, and is the fuel mapped with the same entries below some degrees/TPS?

 

I found part of the answer to my question in the chart you posted earlier, but also this comment you had made at the time:

 

" That is what I feared.

.....

The only hints that is critical are the degrees not matching the volts and on MPH's chart it says,

"Anything below 4 degrees open ECU considers bike to be at idle (as seen by 'flag' on diagnostic program)"

But that is probably just a useless 'feature' of the diagnostic software and not the ECU, and not an invitation to set idle to 4 degrees." "