The Honda PCX / Forza / ADV150 / SH Forums

This is technically a piggy back Fuel Injection controller. If you're really thinking about build a motor this is something you may want to invest in, until they actually make a Full Standalone ECU.

http://www.yuminashi.eu/pgm-fi-controll ... rrencyId=3

dem0nk1d wrote:This is technically a piggy back Fuel Injection controller. If you're really thinking about build a motor this is something you may want to invest in, until they actually make a Full Standalone ECU. http://www.yuminashi.eu/pgm-fi-controll ... rrencyId=3

I think they need to update their prices shown at the bottom of that page (I know you can see the price in your currency against any product)
164 ULTIMATE SET (MSX/GROM125) 2015 (5) $18439.60
USB PGMA-FI PROGRAMMER CABLE $1287.97
INERTIA POWER BOOSTER SET (6) $858.65

dem0nk1d wrote:This is technically a piggy back Fuel Injection controller. If you're really thinking about build a motor this is something you may want to invest in, until they actually make a Full Standalone ECU.

http://www.yuminashi.eu/pgm-fi-controll ... rrencyId=3

I think that standalone dream will be never be fulfilled. The esp line ECU is too complex because it integrates the starting rotor and etc.
It's highly possible it's an apitech efi advance 2.2, no real problem with that though. I talked to Reggy and he seems to have spend a lot of time developing a plug and play fuel controller. For others buying this equals getting a wideband o2 sensor which means another 150$

Good find Dem0nk1d
It was not available earlier, but it was absent from Yuminsahi's portfolio for some time.
The Yuminashi controller is indeed a rebranded API Tech 2.2 piggyback, but nevertheless it is a capable device. Not as sophisticated as others, but it does the job done. However it is still using the narrowband lambda sensor - which is insufficient for scenarios outside of seeking for AFR 14,7. And as the stock ECU is still trying to compensate to stoich AF mix during closed loop operation (below 80% load) it will throw that out on the window. So serious tuners should either completely disconnect the narrowband sensor, or use a wideband and shift the simulated NB output to a different working point. The earlier though would end up in a check engine light going off pretty soon.

Keep in mind, that the pcx has a more sophisticated control system than a CBR or a Grom for instance. It has the dynastarter including the crank position sensor and an integrated charge controller, and also utilises a MAP sensor (Manifold Absolute Pressure to have more sophisticated load sensing than just TPS) and an IACV (Idle Air Control Valve).
A standalone could be still done - if anyone could effectively crack and reprogram the original Honda ECU of the PCX.

Dobeck Performace's AFR+ is a bit more competent solution as it is load based (not RPM only) and uses a wideband sensor to foul the ecu during closed loop operation.
There are other piggybacks also available - like Bazzaz and Power Commander V. which both have external units for autotune to desired AFR rates.

I might spend some time and create a table to compare the specifics of the different fuel contollers.

Reggy said only the PCX150 has the problem of leaning out and riching up at the wrong time, other 125 esp ECU are fine with a bigger injector.
For me the choice seems to be pretty clear.
Low cost, plug and play => Yuminashi or APITech.
Sophisticated systems for serious tuners => Bazzaz or PCV, if you can get the autotune thing then no more question really.
Only 1 bugging question.
Installing a larger injector does make sense, in a way, that with the same pressure, the same time the injector is hold opened, a larger flow will inject more fuel, but does the fuel being sprayed get more liquid? As I understand, you would want fuel to be emulsified with air to make it more combustible.
With the same pressure applied, at which point do we have to upgrade the fuel pump, this would be a totally different topic because the check engine light will be on the moment we connect the new stronger fuel pump. Reggy himself said that using bigger injectors would one day require a new fuel pump.
I'm running a 125 bored up to 150, with the 8 hole big bore injector, and when I twist the throttle suddenly or WOT, there would be a substantial delay/hiccup/hesitation before the engine revs up. Is this a sign of too much fuel being delivered or too little fuel being delivered or because I did not upgrade my intake side (same throttle body and manifold, same 125 air filter), my engine is actually running TOO RICH now?

With all respect, Reggy is running a great marketing company rebranding products from other manufacturers. This is still great - many others does this.
The riching and leaning is a function of the parts used and it is always relative.
The leaning is caused by the fact that the factory ecu keeps a stoich 14.7 AFR at idle and cruise what is combined with the very high compression of the yuminashi kit is actually very lean relatively. The same air fuel ratio is absolutely OK for the lower factory compression. As it is continuously adjusted through the feedback mechanism through the factory lambda sensor this is not compensated by the larger fuel injector at all as the ECU will trim down injection times as it "learns" the new setup.
As the factory uses a narrow band lambda sensor (what can only detect around 14.7 AFR, or more prcisely it detects if the AFR is lower or higher than this value) it has to use a "blind" or open loop operation at WOT and high engine load. As this is not adjusted, but a set value - a seriously oversized injector will deliver too much fuel in this conditions. The combination of the above means the engine will run both relatively lean in certain conditions and rich in others.
Keep in mind that unless the APItech/Yuminashi unit alters the existing lambda signals the engine will still try to compensate to lambda1 resulting in inconsistent closed loop fueling.

The factory fuel pump is still OK for even the largest possible PCX engines - the Grom guys have 235cc kits and still running on their original fuel pumps. This is also because the fuel is not injected directly to the combustion chamber, but rather on the back of the hot intake valves - providing both cooling and evaporation of the fuel.

As for your specific setup the only way to tell what conditions your engine operates would be to hook up a wideband Lambda sensor, or read the spark plug.

Oyabun wrote:With all respect, Reggy is running a great marketing company rebranding products from other manufacturers. This is still great - many others does this.
The riching and leaning is a function of the parts used and it is always relative.
The leaning is caused by the fact that the factory ecu keeps a stoich 14.7 AFR at idle and cruise what is combined with the very high compression of the yuminashi kit is actually very lean relatively. The same air fuel ratio is absolutely OK for the lower factory compression. As it is continuously adjusted through the feedback mechanism through the factory lambda sensor this is not compensated by the larger fuel injector at all as the ECU will trim down injection times as it "learns" the new setup.
As the factory uses a narrow band lambda sensor (what can only detect around 14.7 AFR, or more prcisely it detects if the AFR is lower or higher than this value) it has to use a "blind" or open loop operation at WOT and high engine load. As this is not adjusted, but a set value - a seriously oversized injector will deliver too much fuel in this conditions. The combination of the above means the engine will run both relatively lean in certain conditions and rich in others.
Keep in mind that unless the APItech/Yuminashi unit alters the existing lambda signals the engine will still try to compensate to lambda1 resulting in inconsistent closed loop fueling.

The factory fuel pump is still OK for even the largest possible PCX engines - the Grom guys have 235cc kits and still running on their original fuel pumps. This is also because the fuel is not injected directly to the combustion chamber, but rather on the back of the hot intake valves - providing both cooling and evaporation of the fuel.

As for your specific setup the only way to tell what conditions your engine operates would be to hook up a wideband Lambda sensor, or read the spark plug.

Tök jó! Glad I could bring a new product to the people. Off subject if you're Hungarian your English is written very well.

dem0nk1d wrote: Tök jó! Glad I could bring a new product to the people. Off subject if you're Hungarian your English is written very well.

THX. I still make quite a lot of mistakes, but I think I can make myself understood usually. Indeed I'm a Hungarian. Sometimes I don't know if I should be proud or ashamed though. ;-)

Oyabun wrote:Good find Dem0nk1d


Dobeck Performace's AFR+ or EJK is a bit more competent solution as it is load based (not RPM only) and uses a wideband sensor to foul the ecu during closed loop operation.
There are other piggybacks also available - like Bazzaz and Power Commander V. which both have external units for autotune to desired AFR rates.

The O2 sensor only works during certain times based on input parameters. I believe they are not used during WOT?

Injectors are HP rated, not flow rated. What injector you used depends on what HP you have. A piggy back unit will adjust the fuel of course.

Don't forget that in three stage units like Two brother Juice box (made by Dobeck) the three stages are Cruise, Acceleration and Full throttle.
Regardless of whether you have more stages in say a PC based system, for a CVT scooter there are only effectively two stages. Cruise and full throttle. There is no "Acceleration" phase in which one has relatively low RPM vs high throttle opening as would be the case with a motorbike. This is of course because the CVT changes gear during acceleration so there is no low RPM vs high throttle opening.

Piggy back fuel controllers will not add speed or performance to stock bikes. Most motorcycle ECUs have enough capacity in them to allow for aftermarket exhausts.

IMHO the stock oxygen sensor is quite limited because they're narrow band which mean they're pretty stupid. Only tell if the AFR is shifting away from 14.7, my mechanic even think about wiring an resistor to increase the output voltage to trick the ECU, I don't have any idea if it's even right theoretically.
At WOT, the O2 sensor actually is ignored by the ECU since there's very little time for the fuel to enter the combustion chamber. IMHO the ECU better be spraying fuel all over the intake manifold to cool the intake valve and have better fuel entering the combustion chamber to avoid engine damage.
I've checked my spark plug. I'm running way too rich, but not enough charge is entering my combustion chamber, worsens the situation. I'll leave it like that for now and wait for my engine rebuild. I steer away from the high performance camshaft though. Would like to see if the 164cc perform on the stock camshaft and to be on the safe side.

With all my respect I have to differ in many points. I have to poit out that I have no issues with you personally - moreover I really value that you are an active and helpful member of the forum - but I hate when the same misconceptions are repeated over and over.

waspmike wrote:The O2 sensor only works during certain times based on input parameters. I believe they are not used during WOT?

The O2 sensor works all the time. It is a simple, single wire zirconia type passive element without a heater or a charge pump. It will generate an output voltage based on a chemical reaction between two zirconia plated ceramic elements in presence of oxygen. As I wrote earlier it has a switching type characteristics, practically having a very steep change curve of 10V/sec to indicate it the exhaust gases are richer or leaner than the preset 14.7 AFR value. This is why the AFR is actually fluctuating at idle and cruise as the ECU cannot set AFR exactly at that working point but continuously overcompensating slightly around the value.
The only input parameter for the O2 sesor is the gas it measures. It is however very sensitive to heat, below 600 deg C it is not providing any useful info, that's why it is placed in the head to keep it up to temperature.
It's signal is neglected by the ECU at WOT.

waspmike wrote:Injectors are HP rated, not flow rated. What injector you used depends on what HP you have.

Please, please don't say this again, because I'll start creaming. I already get cranked when the injectors are described as "6 hole large injector" for instance. It is certainly helps to identify them in one' parts box or drawer, but have nothing to do with the capacity of the unit. Only uneducated shadetree trial-and-error backyard mechanics (or in fact parts guys working with them) would call an injector HP rated - as it is completely false.
A given injector will not change the HP of an engine, therefore it cannot be identified or rated by that. There are many parameters to describe an injector (like maximum duty cycle, max operation pressure, flow rare, impedance, drive circuit type etc.) - but HP is not of them. The only parameter that can practically enable comparing two injectors is flow rate per time unit at a given pressure (usually cc/sec, grams/min or lbs/hour on 2 or 3 bars). Maximum HP rating is specific to an application (overall engine efficiency with the maximum fuel delivered at an RPM) and not to an injector.

Let me just use the example of BPT's case right above. He is currently using a larger injector than he should in his current setup. During the closed loop operation the injector hasn't changed the horsepower of the engine, as it is compensating the extra flow by providing shorter injection time. In the open loop portion where due to lack of usable feedback from the O2 sensor the injection times are fixed it dumps way more fuel than needed - therefore actually he gets less power than he could with a properly sized setup.
Also an undersized injector might not be deliver enough fuel even at 10% duty cycle at high RPM therefore limit reachable HP, but then in the automotive tuning industry it is very common to use variable rate fuel pressure regulators, and with increased pressure it might easily deliver 20 or even 40% more fuel - resulting in more HP.
On the other hand if BPT would have the right information on injector flow rate and could select the right injector to his application, he could for example select a proper injector what delivers exactly 20% (150-125)/125=20%) more fuel than the factory one and would be more or less spot on with his fueling at WOT.
I hope it is clear now why it is understandable why it important to use the right measures when planning to work on an engine.

waspmike wrote:A piggy back unit will adjust the fuel of course.

Not all piggybacks are altering fueling directly. In fact it directly adjusting fueling may not work at all in certain applications.
As I wrote above during closed loop operation the ecu compensates for any deviation from it's set working point. Therefore it is completely useless and would lead to inconsistent fueling to adjust fueling directly. In this part of the operation the only way to have a consistent solution with a piggyback is to alter the O2 signal feedback to the ECU. As the narrowband (NB) sensor will not be able to detect such conditions a wideband (WB) sensor is needed with the proper programming. The easiest solution is to have a WB contoller installed and change the switchover point set to a different AFR - eg. 13,5. This way the feedback is still working towards the ECU and it will control the operation by adjusting fueling to the new setting. It is very important, as the ECU has the extra sensors (e.g. cylinder head temp, intake air temp, manifold absolute pressure and ambient air pressure) to be able to compensate for other minor external factors which are not cared for by a piggyback controller.
Outside of the closed loop operation envelope it is true though that the only way to alter fueling is to directly modify injection length to deliver more or less fuel than the factory preset values would allow.

waspmike wrote:Don't forget that in three stage units like Two brother Juice box (made by Dobeck) the three stages are Cruise, Acceleration and Full throttle.
Regardless of whether you have more stages in say a PC based system, for a CVT scooter there are only effectively two stages. Cruise and full throttle. There is no "Acceleration" phase in which one has relatively low RPM vs high throttle opening as would be the case with a motorbike. This is of course because the CVT changes gear during acceleration so there is no low RPM vs high throttle opening.

Generalization, what does not seem to hold firmly. I have made quite long data logging sessions before started modifying my bike and found that 5-15% of my riding is in fact in slow acceleration, or mid load phase. These are typically around mid speed (30-45miles, or 40-70km/h) where I either only have to accelerate slowly or going slightly uphill and the engine is under increased load but the variator does not change gears.
Therefore I would not rule out using a properly set up fuel controller for acceleration stage either.

waspmike wrote:Piggy back fuel controllers will not add speed or performance to stock bikes. Most motorcycle ECUs have enough capacity in them to allow for aftermarket exhausts.

This is also a common misconception, and also a generalization as different piggybacks are working differently, therefore not necessary true.

First of all in case the top speed is limited by power (the engine does not hit the rev limiter at top speed which is the case with the 125 on level road) actually increasing the power output at the top RPM range will change top speed AND acceleration.
Let me cite a dyno chart from Akrapovic. It shows charts of both the stock and an aftermarket exhaust - no other changes and fueling is still stock and provided without any adjustments. One can see, that this simple change will effectively change the top end power curve of the bike, effectively raising the top speed reachable.
How it works. As the variator cannot adjust to spin the engine at the RPM with max power at all times (it will lock out at a point and from there any increase of speed can be only reached by raising the engine revolutions) on less powerful bikes the max speed will be reached before hitting the rev limiter as at that point the engine is not able to provide enough power to accelerate further. If high revs power is raised - the flat road top speed will be raised also as the bike will accelerate further with more power available. On the attached dyno chart one can see also, that 0-100km/h accelaretion is shorther by 1 second (down to 15 from 16) which might not be a lot - but it is a change. If fuel would be compensated to the increased flow - even more changes could be realized as we have discussed that stock ECUs are not compensating for fuel in open loop mode.
Second. Most fuel controllers are able to raise the rev limiter, so in case the top speed is limited by the rev limiter and the transmission gearing (like it is on a PCX150 on a level road, or on a 125 on a downhill) an increase from 9.500 to 10.000 RPM can actually raise the top speed even on an otherwise stock scooter.
Now if the second rev limit raising version is healthy or not on a stock engine - is a different question - but it is definitely able to change top speed and performance.

BPT7594 wrote: I've checked my spark plug. I'm running way too rich, but not enough charge is entering my combustion chamber, worsens the situation. I'll leave it like that for now and wait for my engine rebuild. I steer away from the high performance camshaft though. Would like to see if the 164cc perform on the stock camshaft and to be on the safe side.

I'd go for a throttle body from a PCX 150, with slightly adjusted and matched intake ports on the 125 head, and a better flowing exhaust. That way you could add more flow (more oxygen to burn the extra fuel) to compensate for the increased amount of fuel and lean out your open loop fueling a bit.

Oyabun wrote:

BPT7594 wrote: I've checked my spark plug. I'm running way too rich, but not enough charge is entering my combustion chamber, worsens the situation. I'll leave it like that for now and wait for my engine rebuild. I steer away from the high performance camshaft though. Would like to see if the 164cc perform on the stock camshaft and to be on the safe side.

I'd go for a throttle body from a PCX 150, with slightly adjusted and matched intake ports on the 125 head, and a better flowing exhaust. That way you could add more flow (more oxygen to burn the extra fuel) to compensate for the increased amount of fuel and lean out your open loop fueling a bit.

I have perhaps the weirdest setup ever.
29/23mm valves, "milling" I think of the combustion dome in the cylinder head to decrease compression ratio a little, high lift camshaft, 58mm piston.
My intake is stock, meaning stock EVERYTHING from the manifold to the throttle body all the way to the freaking air filter, only a bigger injector, more on that later.
My exhaust is the contrast. Waaaaaay more free flow than I need I think, I had a SBK carbon 2011 with a modded pipe, great power but too much noise, even with a modded quiet insert. Drop that, modded the stock exhaust, now I think it's way too much.

My problem is definitely the injector, because I have 2 different B type 8 hole fuel injectors. One with 2 half circles, look like a bite mark. One that looks like a hexagon
I recently drop in the bite mark one, which I think is too much. I'll replace it with the hexagon one and update. I've tried tuning some carbureted small size engines. You can be too rich, almost had an engine dying on me because of too much fuel contaminating the oil by blow by

Oyabun wrote: Please, please don't say this again, because I'll start creaming.

Please tell me you mean "screaming" because otherwise it would be very awkward

Bloody autocorrect. :-)

I'll get back to you as I have to dash out. Not all you say again is not 100% correct.

Injectors are rated for flow not hp. I guess you could look at it this way.
http://www.docinjector.com/info1.htm

waspmike wrote:I'll get back to you as I have to dash out. Not all you say again is not 100% correct.

What I wrote I really mean and base on my engineerinf studies and currnt uderstanding of engine management systems.
HoweverdI'd be happy to admit ifmI'm mistaken and open to a challenging discussion, but please support your point with facts - just as I did.

I wonder...where did Vlad go?
And did maddiedog sell his PCX?
Am I too late to this forum?

Never too late.
Maddie indeed sold his PCX and hasn't even logged in recently.
Vlad got very busy in business ventures, so he did not fiddle with his "angry chainsaw" lately.