Plug & Play Fuel Gizmo

[smallj]

Any word from Boxercup on availability of this?

[Guest24]

That would depend on what THIS is.

[smallj]

This would be the modulator that mentioned here...

Anything from Foster on the "Modulator"

[2wheelmike]

I emailed Robert two weeks ago and again yesterday, but no reply.

[Bob Hancock]

I'm waiting too. Been ringing his bell whenever I get a chance but he's evidently busy with other stuff.

[Peter Parts]

The Motronic 2.4 runs either in map/logic mode OR feedback mode using the O2 sensor (AKA closed-loop). Outside very stable times on the superslab, it rarely goes to feedback mode.

In feedback mode, some riders get surging because, some feel, the mixture is too lean and/or the ECU hunts for the right mixture. This can be corrected with a "pot" that is added to the O2 circuit; it fools the ECU into thinking the mixture is leaner than it really is. More common in Europe. My suspicion is that careful tuning resolves surging.

The gizmo may act like some kind of sophisticated pot add-on. In which case, it is beneficial only when in feedback mode. This is my best guess from the minuscule information available.

It is possible the gizmo reads the O2 sensor at all times and during map/logic mode, fools the ECU in some way - such as by fabricating air or oil temperature readings. The Motronic doesn't react too strongly to these temperature inputs except at extreme temperatures (which may explain the PCIII starting issues).

Maybe the gizmo enlarges the spray duration during all modes (it can't ever tell what mode the ECU is in, of course) whenever it thinks the mix is lean, like a Techlusion. But, like a Techlusion, it can't shorten the spray.

Or maybe it is a whole different and cleverer design.

[lht]

Interesting, did you install one on your bike? If so how and what is the Gismo?

Thanks

[Peter Parts]

Originally Posted by lht

Interesting, did you install one on your bike? If so how and what is the Gismo?

Thanks

Have no personal knowledge of the gizmo and found no enlightenment at ForsterRad's website. Was really trying to put some good order on things said in the earlier dead thread based on the fact that I seem to be the only person to ride around with an A/F meter and bothered to write about it for others.

Where I say "may" or "it is possible" or "maybe" that is exactly what I mean. Possibly I have some other product in mind as a basis of comparison. Where I don't qualify that way, I don't think I am guessing. But might be.

Glad to be corrected by anybody who knows more.

[shreddr]

im so surprised...

[roger albert]

> I seem to be the only person to ride around with an A/F meter and bothered to write about it for others.

Plenty of people have. It's been written here before too. Some of you newish guys seem to think just because you haven't seen it, it hasn't been covered. It has.

Also, the motronic ends up in closed loop pretty often.

[Peter Parts]

Originally Posted by roger albert

snip

Also, the motronic ends up in closed loop pretty often.

By what means do you detect that a bike is in closed loop mode?

[throttlemeister]

Ben, do a search on powercommander and a/f meter.

[Peter Parts]

Originally Posted by throttlemeister

Ben, do a search on powercommander and a/f meter.

Thanks TM.

I am acquainted with that information. It describes (within limits of proprietary-talk) when the PC will move from map/logic mode into closed loop mode and back. That's theory, you might say. So there is the further disconnect between their operating model and how the ECU behaves on the road.

The usual inertial dyno can't tell you because you are always accelerating ("inertia," right) and that keeps you always in map/logic mode.

My question is: how do you actually detect when your ECU has shifted to closed loop mode?

[throttlemeister]

There are several threads with people describing the use of the optional A/F meter mounted on the bike that hooks up to the PCIII and wideband O2 sensor to see behavior on the road. They all describe the system going into closed loop almost immediately (< 1 second) as soon as they stop accelerating, as their A/F needle immediately jumps to the A/F ratio set in the PC (typically 13.8).

Also, the PCIII does not go into open loop or closed loop mode by itself. It is a piggyback system, so it can only go into either mode if and when the Motronic does. Motronic is the master and dictates operation.

[Bob Hancock]

Originally Posted by Peter Parts

By what means do you detect that a bike is in closed loop mode?

Candygram for Mongo?

[Peter Parts]

Originally Posted by throttlemeister

There are several threads with people describing the use of the optional A/F meter mounted on the bike that hooks up to the PCIII and wideband O2 sensor to see behavior on the road. They all describe the system going into closed loop almost immediately (< 1 second) as soon as they stop accelerating, as their A/F needle immediately jumps to the A/F ratio set in the PC (typically 13.8).

Also, the PCIII does not go into open loop or closed loop mode by itself. It is a piggyback system, so it can only go into either mode if and when the Motronic does. Motronic is the master and dictates operation.

TM -

I've never seen those posts about tests riders have run (besides my write-up) and can't find them - which doesn't mean much. Took your earlier suggestion about searching but "PCIII" yields 199 threads and "A/F" is an illegal search term and no Boolean searches supported (I taught in the computer science faculty, pardon my geek language).

Can you help the folks out here find those posts?

[roger albert]

Peter,

the lack of boolean searchs stumps me here all the time too.
Greatly reduces the utility of the board. Too much manual searching and filtering.
Sorry, but I don't have a pointer. Too many for me to begin to remember. But if you look at an AF meter, it's just as TM says. It's pretty obvious. Basically, if you're close to stoich, then you're probably in closed loop. (much leaner than stoich can also be closed loop, wherein fuel is cut for emissions/economy, but normally, stoich = closed loop)

Yes, I know that does't help much. Just kinda restates the obvious, and affirms the search options wank.

[Peter Parts]

My thanks to Throttlemeister for his (mostly) helpful description and to Roger for encouraging me to search further. Also I had a phone chat with a fellow in Las Vegas who is a senior manager of DynoJet-PC.

I was mistaken. There are several posts about PCIII users riding with their A/F meters although the reports aren't well structured. But it's not too useful to ride around with a PCIII and A/F meter because it can only establish that the PCIII is working as designed and therefore keeping the A/F on 13.8 or whatever criterion was set - at least whenever the bike is in the map "gray" zone (below 6500 rpm, etc.).

The PCIII over-rides the ECU and has total control of the injectors (and that includes neglecting all ECU load information as Roger pointed out... unlike the Techlusion). The PCIII just keeps to the set-point and for better or for worse, that's that.

I can't say if things are different during acceleration. But they ought to be. If the PCIII goes to a map, then it must be on the map for the duration of acceleration and for enough time afterwards to establish in its own little mind that acceleration has ended, or so it seems to me.

For sure, hard to tell much by looking at the PC A/F meter because it probably hops around during acceleration (I don't know what kind of damping/averaging/time-sampling is internal to the PC A/F meter but it must have some). The Motronic falls back to map mode during acceleration or whenever the throttle is bumped - otherwise, it couldn't be responding to load (duh).

Can't understand if or how the PCIII maps and throttle off-sets influence closed-loop A/F. Aside from riding in the extreme speed or PCIII "white" zone, why would you need different maps for different exhaust systems? The concepts seem in conflict. Any help appreciated.

The Motronic 2.4 ECU is programmed nothing like that. As far as I can tell, pending further searching, there appear to be no realistic A/F results for the Motronic besides mine (aside from inertial dyno traces that aren't applicable to closed-loop operating). Although the ECU is programmed to head for closed-loop operation, I think it rarely gets there. In my observations, the Motronic 2.4 goes closed-loop only for long, dull stretches of road.

And now back to the FosterRad gizmo.

[roger albert]

Again, the Motronic is most often in closed loop. It's obvious from looking at A/F traces.

> Can't understand if or how the PCIII maps and throttle off-sets influence closed-loop A/F. Aside from riding in the extreme speed or PCIII "white" zone, why would you need different maps for different exhaust systems? The concepts seem in conflict. Any help appreciated.

Peter, you're really missing how the Motronic and PCIII operate. You'll always need different maps for different exhausts, because the motronic has no idea how much air is coming in for anything except the amount inferred for exactly the factory system. the PCIII only further manually tweaks (via tables) that fixed, dumb output. This has been covered here many many many times. I mean this in a nice way, but the above question means you don't know how this system, or _any_ alpha-N system works, or, as we can all do when trying to delve deeper, have got caught up chasing your tail in it a bit. Different systems have different airflow and thus require different maps. Do NOT look at the lambda sensor as providing feedback. It does, but only for fine tuning something already properly manually mapped.

[Peter Parts]

Originally Posted by roger albert

Again, the Motronic is most often in closed loop. It's obvious from looking at A/F traces.

> Can't understand if or how the PCIII maps and throttle off-sets influence closed-loop A/F. Aside from riding in the extreme speed or PCIII "white" zone, why would you need different maps for different exhaust systems? The concepts seem in conflict. Any help appreciated.

Peter, you're really missing how the Motronic and PCIII operate. You'll always need different maps for different exhausts, because the motronic has no idea how much air is coming in for anything except the amount inferred for exactly the factory system. the PCIII only further manually tweaks (via tables) that fixed, dumb output.
snip

1. Can you please post one of those traces or provide a link?

2. Don't think I need an explanation of how the Motronic works just now. But can you provide a brief explanation of how the feedback system in the PCIII integrates with a map. Please correct me, but when I was on staff at Bell Labs, we used to think it was one mode (feedback control to a set-point) or some other mode (like map/logic)? Or, as I suspect is the case, does the map provide separate feedback set-point off-sets for each cell in the "gray" zone if running the slider A/F set-point is not close enough?

Much appreciated.