I've answered some of my own questions.

The system adjusts voltage across the board. You set in mA how much you want to increase/decrease. That change is applied to the entire fuel map. A lot of grom guys run this to compensate for exhaust and intake. I'm going to do it. Need to weld a bung on my stock exhaust for my wide band, will log before and after installing the EFIE. This seems like a good option for guys who want to richen up the stock lean AFR and add a pipe and intake.

https://docs.google.com/document/d/1wX0fOAMqEmYk6jgRK37Qc4apUxoLQw5pchcSt5krOFA/edit


Check out post 88:
https://www.hondagrom.net/forums/13-grom-performance/3113-o2-sensor-grom-piggyback-tuners-9.html

 

No one is running this? It seems like an awesome option for guys who just want a pipe and intake. I ordered one. No idea when it shows. Would love to talk to someone who has installed on a Z I know you're out there!!!

 

Have you received it yet if so any difference?

 

Subscribed !

I'm Putting on a custom made up-pipe exhaust next week, And only for ground clearance issues, not looking for any performance gains , but do not want to run lean . I Read the links so got a slight feel for what it is but I refuse to hook a laptop up to a motorcycle ..... following....
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Ya, Old School n ain't change'n

 

The EFIE came today. Shipping estimate was 6 weeks but it took 6 days.

Here are some pics, it is wrapped up in something that feels like large format electrical tape. It came with a note. When you buy it you get an account. There are portions of their website that you can only view with an account and the note said there are updated instructions there. Haven't checked it out yet, it is 8:22 my time and haven't made dinner yet.

Now I only need a bike to install it in. Welder is supposed to show up tomorrow.

Edit sorry for potato quality not sure what happened there.

https://www.z125owners.com/forum/attachment.php?attachmentid=20015&thumb=1
https://www.z125owners.com/forum/attachment.php?attachmentid=20013&thumb=1

 

Did you ever wired it up?
I just put a High flow air filter on and this still sounds like a legit way to richen up a simple intake and exhaust bike up enough to run safe for 30 bucks !

 

Not yet Ka'wee... welding skills not up to par yet to install a spacer and a bung without leaks... maybe I should just take it to the shop.

 

Some info from TOCE Performance who offers to re-flash stock ECUs (my initial email to them in BOLD):

Some confusion here as to closed vs open loop and I did not get all the info I was looking for... I plan to visit and ask some more questions. Info on stock AFR is interesting... 13.0 AFR is what I thought target should be looks like I was pretty close, at least according to these guys.

Still not clear when the bike is in open or closed loop. This is the biggest concern with running EFIE device. If stock ECU reverts to an open loop map at WOT then you are going to be running super lean cruising at high revs which is probably worst case scenario in terms of engine life.


1. What is the target AFR you set the computer for?

The target AFR changes slightly thought the RPM band. But this bike in particular runs about a 13.2-13.4 from idle most the way up then richens up to around 13-13.2 AFR at WOT just for the added "insurance" of keeping everything nice and cool. These Bikes being such a small single cylinder motor perform better in this range, where as a R1 for example likes it a bit richer at 100% throttle at high rpm like 12.8-12.9

2. You have options to delete or keep the O2 sensor. If kept, is the system running in a closed loop for AFR detection? If so is the system ALWAYS in a closed loop or are there spots (idle? WOT?) where the system reverts to Open loop? I don’t think the O2 sensor is a wideband so I am not clear how your ECU flash would work while retaining a narrow band O2.

We do have an option to delete the o2 sensor, and do recommend it especially if you are local to us, because we have created the map to run at our sea level so it will be spot on. The system is always in a closed loop, because the o2 sensor really dosen't exist to the bike anymore so it would have nothing to read off of. The ECU in the bike has different maps it runs off of for different instances, an example would be a cold start at idle it measures the intake temps vs engine temp and knows its cold so it has an enrichment map that it would use until operating temp is achieved. The o2 sensor is in fact a narrow band, so it uses voltage to calculate the "afr" and does not have nearly the capabilities that we are used to seeing with wideband o2 sensors. If you chose to leave the o2 sensor on, the factory sensor would work just the same as it did while it was stock, because we are re calibrating the binary in the ecu, the bike has no idea that its actually been flashed and just makes its "corrections" as it normally would on any other factory map. There is no harm leaving it on there, but we have noticed better gains with it off because stock the z125 runs extremely lean in the higher up rpms and will always be trying to correct its self back to that.

3. Along the same lines, would the reflash work on an otherwise stock bike without causing it to run overly rich?

Yes, the flash will work fine on an otherwise stock bike. We do at least recommend the exhaust, being that the map was created with the intention of using our exhaust. As previously stated the z125 runs shockingly lean especially at higher up rpms (14.3-14.6ish) so we felt as though it is a better option all the way around to richen it up quite a bit, not only for the gains that are achieved, but mostly because these bikes operate generally at wot or close to it and we don't want to see anyone melting down their pistons from really working these little motors, which i have read a lot about on the forums.

4. Do you bring back some of the advance that Kawi removed with their ECU update?

As i am not aware of what "advance" you are referring to, we did give it some more timing at wot to help get a little more horsepower out of these bikes. Our flashes are based off of the newest Kawasaki Binary, so with that we are putting the latest ecu "updated" maps into the bike, but with our fuel and ignition calibration. Our maps do have the cold start and idle fix that plagued the earlier model z125s so that would be a great feature for someone who dosen't have a brand new bike.

I work down the street from you guys and could stop in if that would be better.

Feel free to stop in anytime. Let us know if you wish to purchase anything from us before hand, so we can make sure we have it available for you when you get here.

I’m considering using an EFIE device that will intercept the signal from the O2 sensor and modulate it… this will allow me to shift Kawi’s stock map, but would only seem to work when the bike is running in a closed loop, and I cannot find any information as to when the bike is running in closed loop vs open loop.

You are welcome to use whatever device you wish to with our exhaust, i would not recommend this coupled with an ECU flash as it really wont net you anything. It would make sense that it will only work in closed loop otherwise its just going to endlessly keep trying to correct its self back to a factory setting while the device is trying to correct it back to your chosen value.

Love your undertail I want to pick one up, how do you mount the license plate? I assume you need to run an integrated tail light as well with that pipe?

The exhaust has a little threaded bracket welded onto the bottom of the muffler that our tag bracket screws right into. If you have seen a GROM or even a CBR600rr, it is the exact same setup on the z125. You do not NEED an integrated taillight, however if you wish to run rear turn signals, it would obviously be mandatory. Plenty of people in the motorcycle world ditch their signals and just use hand signals for turning. That is a matter of your preference and budget.

Does your intake include provisions to support the fairing (side fairings attach to stock air box which gets deleted with intake install)?

Unlike the GROM where the fairings are directly supported by the airbox, the z125 actually has its own mounts for the fairings to be held firmly and therefore the rod that is included in our GROM kits as well as many other brands simply isn't necessary for this bike.

If you have any other questions, you are more then welcome to email Ryan@toceperformance.com, or call and ask for Ryan and i will do my best to answer any other questions you may have. Thank you for your interest i hope to speak with you in the future. -Ryan

 

Still not clear when the bike is in open or closed loop. This is the biggest concern with running EFIE device. If stock ECU reverts to an open loop map at WOT then you are going to be running super lean cruising at high revs which is probably worst case scenario in terms of engine life.



2. You have options to delete or keep the O2 sensor. If kept, is the system running in a closed loop for AFR detection? If so is the system ALWAYS in a closed loop or are there spots (idle? WOT?) where the system reverts to Open loop? I don’t think the O2 sensor is a wideband so I am not clear how your ECU flash would work while retaining a narrow band O2.

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My understanding so far is ....
https://www.z125owners.com/forum/wh...-did-you-do-your-kawasaki-z125-today/15471-klx110-exhaust-mod-3.html#post118309
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i'm running a pipe and slightly better intake with NO- 02 sensor (unplugged) and its running better than it ever has using only the stock ECU
https://www.z125owners.com/forum/wh...-did-you-do-your-kawasaki-z125-today/15471-klx110-exhaust-mod-2.html#post118241
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but still wondering if i can use the EFIE to richen across the board ?
Right now i dont think so because without the heat sensor from the 02' saying it is at 600 degrees it will stay in open loop .

 

Ummm... Narrow band running at 13.x:1 will not read any variation. At 14.7-ish it will oscillate between less than 1 volt and more than 1 volt output as the mixture varies SLIGHTLY. https://www.a-i-e.com.au/tech_stuff/view/6974/narrow_band_oxygen_sensors

This make me doubt everything they just said since a narrow band can't really do anything once it gets that rich, you will just be producing 1.xx volts and the computer can't know what is happening.

Also closed loop is running through control, open loop has no control from the o2 input, again refer to the link above.

 

Yeah... I think he typed it out quick and messed up a bit... this Ryan guy is their welder. I'm going to head in and talk to someone. Not ready to give up on the ECU reflash just yet need some more info.

I think deleting the 02 is the only way to make it work correctly and have the system run in OPEN loop the whole time.

 

According to this guy at Toce the bikes run a separate richer map (ie choke mode) until engine is up to temp then switches to normal map. without the O2 present the bike is obviously in open loop... maybe it runs the richer map by default to prevent damage? I have no idea. Guess it doesn't matter in any event because it seems the bike richens up without the O2 sensor in.

But my understanding of how open loop works is that it just runs whatever settings are flashed to the ECU and it doesn't matter at all what the O2 sensor reads. If the bike is running closed loop the EFIE device will be able to shift stock AFR richer or leaner by intercepting and modulating voltage received from the O2 sensor and sent to the ECU. But in cases where the system switches to open loop you are stuck with what kawi gives you because in open loop the modulated signal from the O2 sensor is irrelevant... and if you have the O2 sensor in, which you would need in order to use the EFIE device, it means you aren't getting the richer "choke" or "crap there is no O2 sensor" map, and you get the factory setting, which according to Toce is north of 14.6 AFR. Combine that with an intake and a pipe and you lean it out even more.

So... to me this argues for full ECU flash or piggy back system... but... I gotta ask... what do your plugs look like?

Mine are grey. Grey and clean and lookin' lean. If you tell me you have a nice toasted marshmallow brown that's a good argument for skipping the EFIE and just removing the O2... although I'm too anal to have CEL lit up all the time. Maybe Fox's black wire trick.

This used to be so much cheaper and easier with jets and needle clips.

 

The Grom forum link suggested that ?
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1. "closed loop" refers to when the ecu does active adjustment based on the o2 sensor, this range is typically between 0-80% throttle on our lil bikes
2. "open loop" refers to when the ecu does NOT do active adjustment based on the o2 sensor but rather the map that it has calculated, this is 80+% throttle. Open loop fuel mapping IS BASED ON CLOSED LOOP AUTO TUNING. That is to say, if the ecu is being tricked into feeding the motor more fuel during closed loop (as it does with the EFIE reducing the voltage output of the o2 sensor), then Open loop fueling will also get a bump in extra fuel. The ECU has a formula to extrapolate out what the o2 sensor has done to fuel trims in closed loop and applies that out into the open loop fueling area of the map.
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Another Member...
it looks like the ecu is adjusting to the EFIE settings even during WOT. i thought it was going to run a set mapping for 80-100% WOT and not get richer.

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Before installing the EFIE my temps on the way home were around 220*F - 230*F with 80* - 90* ambient temps. I ride my GROM pretty hard and I'm full throttle 1st - 3rd.
After the EFIE I instantly noticed an increase in power in the mid range and my temps now are 205*F - 215*F with the same ambient temps.
.......................................................................................
.

but... I gotta ask... what do your plugs look like?

Mine are grey. Grey and clean and lookin' lean. If you tell me you have a nice toasted marshmallow brown that's a good argument for skipping the EFIE and just removing the O2... although I'm too anal to have CEL lit up all the time. Maybe Fox's black wire trick.

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I just pulled the plug (see pics) what do you guys think ?
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I wanted to ride my bike for a while before i made the Statement That ...
My bike is defiantly running cooler ! and the EFIE does that !
My bike is defiantly running stronger I instantly noticed an increase in power in the mid range and the EFIE does that !
If anything i notice a very slight blubber at around 4000rpm steady throttle . not always and VERY SLIGHT !
My bike has absolutely zero Decel Pop , even after long WOT and chop the throttle / But right after pipe install and 02 unplugged my first 10-20 miles or so it had Crazy amount of Decel Pop , but then i think the ECU corrected itself even with the 02' unplugged because theres NO/ZERO decel pop now at all
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Also, there is NO black soot what so ever in my tail pipe, cant even get any on my finger from inside .

 

Open loop should still obey what the fuel trims have been set to, just that the trims will not be changed during open loop.

 

Yes Greg agree... the problem is that the fuel trims flashed to stock ECU are set too lean so with EFIE and O2 sensor you would end up richer across the board with the exception of WOT.

The exception to this would be if the stock ECU's "open loop" fuel trims were set dynamically... learned from 02 sensor and subject to change as the ECU learns the settings of your individual bike. I doubt this is the case and tend to believe that they are static... set from the factory and never change. This is admittedly just conjecture on my part. But it would seem that in the case of a malfunctioning O2 sensor they would want a static baseline to fall back on to prevent damage.

 

With modern fuels, reading plugs gets harder. All the additives make the insulator cleaner on average.

I can't decide if I see some shrouding on that plug from the ground strap or not. I'm tempted to index mine when it comes out.

Closed loop is where the trims are set as well as added to the programmed value, open loop the trims are added to the programmed value. These fuel foolers can often screw up your trims which causes the full throttle (open loop) to go way lean. Had a Dobeck what'samacallit on my Buell and it really screwed it over. Not sure how the EFIE works but I've seen plenty of people suggest they work pretty well, even on bikes that still have closed loop functional.

Why they work might be down to the limits set for the trim function. If you change intake and exhaust, then the trims may not be allowed to go far enough to fully cover the changes. Since the EFEI adds duration to the pulses driving the injector, it may add that little extra needed to let the fuel trims stay in their allowed range. Fuel trims on some vehicles are limited to 85-90% through 125% which generally covers their intended working conditions through elevation changes to about 10,000 feet (maybe slightly more) and atmospheric changes in pressure. Generally.

I hope someone cracks the factory ECM programming and gives us a cheap application to allow tuning, otherwise if I ever get where I'm modding for performance it will be a Hoedar ECM so I have full control over timing and fuel.

 

My reservation, after a lot of googleing, is that in some vehicles closed loop trim seems to affect the open loop map, but in some vehicles it doesn't. Based on the forum post I linked to it looks like the Grom will adjust open loop fueling to long term closed loop trims. We don't know that the kawi ECU works the same way.

I'm going to swallow my pride and take stock exhaust to the muffler shop and have them weld on a full size bung and spacer so I can use my wideband and take some WOT AFRs, then install install EFIE and try to get general AFR around 13.4. Take the bike for a long ride then check WOT AFRs... if they change we know we're good... and no lean risk as my bike is still pretty much stock.

Kaw'ee I think your plugs look just a touch rich, but way better than mine with stock setup. I'll throw some pics up of mine later.

Greg I hope you are right about how the trims get added to baseline on open loop... will save people a lot of money if this works.

 

What a guy!

Your wideband will probably still read correctly even if you botch it and create an exhaust leak... just sayin. Only way to learn is to practice, sometimes that results in failure, no big deal. I believe in you!

 

Here's my plug.

I like yours better.

 

OK I got the wideband in today. Put together a little PDF let me know if you guys can't see it for some reason. The file size limit here is 20k I've got ASCII art larger than that lol.

https://www.pdfhost.net/index.php?Action=Download&File=69942922d7e2d9518133b98e54464be6

 

Now thats a top notch report :wink2:
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good to know I'm probably not running lean with a aftermarket pipe and slightly open intake :grin2:
so I'm staying as is for now ,

I thought the blubber i stated at 4000rpm was a rich blubber, but looks like its a lean starve ,
Then again My butt's lied to me before . It's hard to tell on a 8hp bike ?

looks like i wont need the expensive fuel controllers and wiring, maps, laptop programming that most dont seem to get quite right anyways.... so i know i never would.

I wont have the benefits of the compensating that come with the 02 but its running great and I dont plan on any other mod's

 

12:1 is actually too rich for max power unless you have like 15% alcohol fuel, might have to run the common 10% alcohol stuff it this bike. That said, you might have been reading rich because the sensor might have been too far into the pipe. My Innovate MT-X wants a 1 inch bung for small tubes like we have, this is what I welded to my KAYO and it worked well until the sensor failed.

I just jumped the gap by feeding more wire into it when I did the KAYO. It's ugly, but I'm a hack so I don't care, was done with a cheap fluxcore welder.

 

Greg- I checked this out this morning on my way to breakfast. I had prepped (2) 1/8" thick washers in case I needed to shim the sensor. I rode to breakfast with 1/8" total shim, then rode home with 1/4" total shim. AFR was unchanged. So I think the bike really does run 12:1 at WOT. Maybe not best for power... but I'd wager Kawi set it up this way to keep temps cooler. Just my guess.

 

You should check the amount of protrusion into the exhaust, the sensor accounts for a pretty big disturbance in these little pipes. The least amount of protrusion that still works is the best way to go.

What fuel are you using? We might want to tune using different amounts of alcohol to get that max power right where we want it. Maybe a little Seafoam or Lucas cleaner added to thin it out. I may need to weld a second bung on my exhaust and do some looking. Start with 90 octane alcohol free and work backwards until I get the power where I want in open loop full throttle and let the computer worry about mid throttle. Assuming I get time for racing next season, want all this stuff worked ahead of time.

 

Need some help boys.

Got EFIE wired up today. Sorta.

There are 4 wires to O2. (2) white which I believe are HEATER circuit, a black which is positive signal (to ECU) and a grey which I THINK is just a ground. But it is a ground that goes back to the ECU.

I intercepted the Black (positive signal wire) with EFIE and set it up so voltage that passed through it was reduce by 0.250 volts. Used multimeter to test I verified that it worked on the bench and once in the bike. I tested the positive signal wire on both sides of the device and all was good.

Fired up the bike and it threw a code. I thought maybe the modified signal was out of range. AFR was whacky. Started high almost 15 then dropped to 12-13. I adjusted the device to drop signal by 0.150 volts and went for a ride. AFRs were mixed. Giving it more throttle the AFRs seemed lower. with the throttle cracked they were 14.2-15. This behavior was similar to running without the O2. Coming off throttle idle would end up around 13 afr then creep up to 14.6ish after maybe 15 seconds. Almost like the system was fighting with itself. Maybe idle is open loop and previously learned trims were coming into play.

After the ride I pulled the code - #67 for O2 heater element. Strange. I checked resistance through the 2 white wires (running to the O2) and got 18 ohms which per manual is in spec. I checked for voltage feeding the heater circuit at the O2 harness and had battery voltage. So I'm not sure why I'm getting heater circuit code. The manual says next step is check continuity to the ECU and if that is good then get a new ecu lol. I think it must just be a fluke code because I didn't mess with ECU or harness wiring. I tapped into O2 harness only.

I was reading 1.2 - 1.35 volts on the positive O2 signal wire before modification, this was giving me AFR readings around 14.2. This is my first time playing with narrow band O2s so I don't know what kind of voltage to expect. I'm measuring positive signal to ground. This may be an important detail. The manual, when testing the O2 positive signal wire voltage, has you connect to the grey wire (the mystery maybe a ground that definitely goes back to ECU) and not just any ground. Not sure if this matters. For more understanding of the ramblings in this paragraph crack open that manual to section 3-62. It is for diagnosing O2 sensor performance. It says connect positive lead of voltmeter to BLACK (check) and negative lead to GREY (I used chassis ground). It then goes on:

(Rich) DC 0.8 V or more
(Lean) DC 0.24 V or less

I'm getting 1.3 V at 14:1... so wtf?

Maybe the negative side actually has some positive voltage that would lower my reading when measuring across the black and grey wires. In any event a 0.250 V drop considering the range of 0.8 - 0.24 may be too much.

Thoughts?

Tonight I disconnected the ECU hoping overnight all fuel trims will be forgotten. Not sure if I should zero out the EFIE and ride it until the CEL clears or just ride for a while with the 0.150 offset.

 

.
Questions are just really trying to learn here more than I'm helping you I'm sure , But maybe something in one of my questions might trigger something for you ?
Dont answer anything that is waaaay of base .. and that answer my question


[[and a grey which I THINK is just a ground. But it is a ground that goes back to the ECU.]
[[ (the mystery maybe a ground that definitely goes back to ECU) and not just any ground.]
[[has you connect to the grey wire (the mystery maybe a ground that definitely goes back to ECU) and not just any ground. Not sure if this matters. For more understanding of the ramblings in this paragraph crack open that manual to section 3-62. It is for diagnosing O2 sensor performance. It says connect positive lead of voltmeter to BLACK (check) and negative lead to GREY (I used chassis ground). It then goes on:]]
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The gray does go to the ECU, (3-63)(page 135)
.
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[[with EFIE and set it up so voltage that passed through it was reduce by 0.250 volts. Used multimeter to test]]
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Reduced? you mean you set it to 250 mv like the grom guys did?
.
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[[I thought maybe the modified signal was out of range]]
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from grom guys ... If we look at a narrow band o2 sensor voltage chart you can see a ~250mv offset will make the switching poing around an afr of ~ 13.3-13.5:1. You can not go much above 350mv decrease as you get to the point of the ecu always seeing 0 volts and this will throw a CEL and not be able to properly lean out and tune to how it wants.
.
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[[Fired up the bike and it threw a code.]] Above statement (from grom guys)
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Is it because you removed the 02 to test on the bench ?
have we ever conformed when CEL comes on after disturbing the 02' that it is for 02 #33 code or for the #67 heater code
.
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[[Coming off throttle idle would end up around 13 afr then creep up to 14.6ish after maybe 15 seconds. Almost like the system was fighting with itself. Maybe idle is open loop and previously learned trims were coming into play.]]
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Like you were thinking WOT would do .. but why would it creep
Did you get a WOT reading.
.
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[[I'm getting 1.3 V at 14:1... so wtf?]]
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because the Gray wire is not going to the ECU
.
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did you take the EFIE gray wire to the 02
and the EFIE green wire to the ECU
Like the grom guys did ?
.
YOU GOT THIS :wink2:

 

Kaw'ee- All comments advice welcome. Thanks for the reply. I took pics of the install I'll throw em up later, but for your questions:

Yes, Grey to ECU, for sure 100%.

Yes, Reduced by 250mv, just like Grom guys, that's why I started with 250.

Thing about the code is I figured it would throw the bad O2 code, not the bad heater circuit. Unless maybe it threw both if I had key to ON position with no O2 present. I grounded the diag port and read the flashes. Is there a procedure to see if there is more than one stored code? I held it grounded and the flashing kept cycling through the 1 code, #67 bad O2 heater circuit.

I did get WOT. It was 12, just like before. Mostly. Saw 11.8, 11.9 as well for the first time. I believe creep may be to stored long term trims???

Your text below:
------------------------------------------------
[[I'm getting 1.3 V at 14:1... so wtf?]]
.
because the Gray wire is not going to the ECU
-------------------------------------------------------
Not sure what this means Grey and Black both go to ECU. Some other forums say sometimes talk about a bias voltage to the O2. This is basically arbitrary voltage the ECU runs through O2 signal circuit. O2 only generates voltage when it gets warm enough. ECU monitors the voltage whenever it is on. So in the beginning O2 is cold, and ECU only sees the bias voltage it is sending. Once O2 warms up the voltage it generates gets added to the bias voltage... the ECU sees the change and uses the difference between bias and read voltage to extrapolate the 0.1 - 0.9 V narrow band swing. This is I think why I am getting voltages over 1.2V on the narrow band signal wire. I will check voltage at the O2 harness connection to main harness without O2 sensor installed to try to confirm there is bias voltage coming into play. This could be why the manual wants you to test signal voltage across the gray and black wires, not just ground and black, so you automatically cancel out the bias voltage. Also I need to do full continuity tests from O2 harness through ECU connection just to make sure... I've had loose wires on this bike before I had to chase down.

Yes, Cut the BLACK signal wire to O2...White EFIE wire to O2 side, Green EFIE wire to ECU side.

Appreciate the vote of confidence. Anyone else have ideas? Sucks I need to go to work and cannot continue to tinker with this sucker.

 

Keep in mind that narrow band o2 is not really an analog signal. They basically switch back and forth between rich and lean, the system never really finds a place and holds. The switching tells the system when things are good, and the system is constantly making adjustments back and forth to get that swing for a check.

I'm wondering if you might want to use the analog output from your wideband to simulate the effect you want, night at least get some understanding of what Kawasaki is doing in the ECU, the EFIE may not work because of this. Kind of an expensive work around to suggest that everyone runs a wideband meter and simulates a narrow band on the output, but it might help us gain some understanding of the stock ECU.

Take a look at this article https://www.a-i-e.com.au/tech_stuff/view/6974/narrow_band_oxygen_sensors