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Does it actually have a Capacitor Discharge Ignition or does it have an Electronic Control Unit that you are calling by the wrong name?
It is pretty common for people (especially in the UK) to refer to any electronic ignition as a CDI whether it creates the spark by discharging a capacitor into the coil's primary winding or not. But no matter how many times lazy people call them by the wrong name it won't turn an ECU or a TI spark unit into a CDI.

BTW: Welcome to the forum. Please add your location and your bike's model and model year (NOT year first registered as UK paperwork shows) to your profile so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).
According to the wiring diagram there is an ECU that controls the injection and a separate spark unit that I thought was a CDI, hence some of the issues with converting it to a speeduino or Mirosquirt since you'd have to get the ignition timing from somewhere. I've seen Rae San does Hall sensors that I thought could work but I'm only in the early stages of planning and looking into the actual feasibility of the whole thing.
 

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1985 Honda Goldwing Limited Edition - 1995 Honda Goldwing GL1500 SE - 2012 Suzuki V-Strom DL1000
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Discussion Starter · #22 ·
Had a look at the Honda Turbocharger/Computerized Fuel Injection Manual to determine if there are similarities between my project and Saint_Orc's/cgc154's. If I were to compare, I would have to say that the 1200 CFI ECU does what the ECU for the CX500 and CX650 turbos. The ignition control unit on page 16 of the CX manual is actually the spark igniter unit for the 1200 CFI ECU. The schematic in the turbo manual is not very well detailed because the CFI ECU needs to control the fuel and ignition of the engine.

So I'm thinking that the ignition control unit shown in the schematic on page 16 of the turbo manual is also controlled by the CFI ECU. I mention this because the coil has to charge/discharge. It charges by having the coil ground go to a path that is easier than going through the plugs. The ignition control unit is grounded to wherever for the coil to charge, this ground is removed, and the coil discharges through the plug(s).

Just a thought or two.
 

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Had a look at the Honda Turbocharger/Computerized Fuel Injection Manual to determine if there are similarities between my project and Saint_Orc's/cgc154's. If I were to compare, I would have to say that the 1200 CFI ECU does what the ECU for the CX500 and CX650 turbos. The ignition control unit on page 16 of the CX manual is actually the spark igniter unit for the 1200 CFI ECU. The schematic in the turbo manual is not very well detailed because the CFI ECU needs to control the fuel and ignition of the engine.

So I'm thinking that the ignition control unit shown in the schematic on page 16 of the turbo manual is also controlled by the CFI ECU. I mention this because the coil has to charge/discharge. It charges by having the coil ground go to a path that is easier than going through the plugs. The ignition control unit is grounded to wherever for the coil to charge, this ground is removed, and the coil discharges through the plug(s).

Just a thought or two.
sounds like a potential rabbit hole.
Recommend the OP go to the turbo tech help section for advise/parts if needed
 

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Discussion Starter · #24 ·
sounds like a potential rabbit hole.
Recommend the OP go to the turbo tech help section for advise/parts if needed
I agree, it is the proverbial rabbit hole. Lots of research to be spent finding out requirements, to learn of the tests and trials of those who may have already ventured down this road.

Even though I agree that this is a daunting endeavour, it is a good project to understand the complexity of the ECU and what component requirements go into making a fuel injection system work, and how everything is interconnected. I settled on the Speeduino Project for my project and there is a lot of information on the Speeduino forum regarding this issue, mostly by people installing a fuel injection system from scratch, not as a replacement for an existing FI system ECU. I found that the main issue with a replacement ECU into an existing system is to keep the functionality the same. In my case, I have to consider the integration of the ECU, travel computer and dash as all three are interconnected.

The sensors used in the Honda FI CFI system are adequate for a Speeduino or Megasquirt application. The injector timing of approximately 0.45 ms (I think the number is correct) is a good starting point for these. A trigger wheel with more teeth is better than less. My trigger wheel on the crankshaft for the Ns signal is 8 teeth and can be used, but a 16 or even a 32 tooth trigger wheel would be better. The PG sensors, mine are called Gr/Gl and are on the end of the right cylinder head, can be used but only one. Honda used two to simulate sequential firing. My CFI system does not use an exhaust sensor, and the Speeduino system does not require one, but it does aid in making the system work as per the newer FI systems especially at idle. Do you want a wasted spark system, or a sequential firing system. The newer ECU systems can be beneficial to the performance of the engine and your ride enjoyment. How does the self-diagnostic program of the early Honda ECUs function and how do you keep this functionality?

Lots of performance add ons such as Power Commanders. These are great interim components but never get to the root of the issue, what is programmed into the OEM ECU. Using larger multi-matrix maps instead of an older 3 by 3, or 4 by 4 matrix fuel map. Being able to plug your tablet into the system, go for a ride, look at the various fuel maps - change a setting here and there to take the bugs out of the system is, for some, what is wanted. The caveat with doing this is that you could do more damage than good, but if the ability to delve into the system, come up with a better mousetrap is what you are after - go for it. Also have a good escape plan such as reverting back to the original.

Never know if one of these projects will ever come to fruition, but it's fun to learn new information and work on projects that interest you.

Cheers
 

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I agree, it is the proverbial rabbit hole. Lots of research to be spent finding out requirements, to learn of the tests and trials of those who may have already ventured down this road.

Even though I agree that this is a daunting endeavour, it is a good project to understand the complexity of the ECU and what component requirements go into making a fuel injection system work, and how everything is interconnected. I settled on the Speeduino Project for my project and there is a lot of information on the Speeduino forum regarding this issue, mostly by people installing a fuel injection system from scratch, not as a replacement for an existing FI system ECU. I found that the main issue with a replacement ECU into an existing system is to keep the functionality the same. In my case, I have to consider the integration of the ECU, travel computer and dash as all three are interconnected.

The sensors used in the Honda FI CFI system are adequate for a Speeduino or Megasquirt application. The injector timing of approximately 0.45 ms (I think the number is correct) is a good starting point for these. A trigger wheel with more teeth is better than less. My trigger wheel on the crankshaft for the Ns signal is 8 teeth and can be used, but a 16 or even a 32 tooth trigger wheel would be better. The PG sensors, mine are called Gr/Gl and are on the end of the right cylinder head, can be used but only one. Honda used two to simulate sequential firing. My CFI system does not use an exhaust sensor, and the Speeduino system does not require one, but it does aid in making the system work as per the newer FI systems especially at idle. Do you want a wasted spark system, or a sequential firing system. The newer ECU systems can be beneficial to the performance of the engine and your ride enjoyment. How does the self-diagnostic program of the early Honda ECUs function and how do you keep this functionality?

Lots of performance add ons such as Power Commanders. These are great interim components but never get to the root of the issue, what is programmed into the OEM ECU. Using larger multi-matrix maps instead of an older 3 by 3, or 4 by 4 matrix fuel map. Being able to plug your tablet into the system, go for a ride, look at the various fuel maps - change a setting here and there to take the bugs out of the system is, for some, what is wanted. The caveat with doing this is that you could do more damage than good, but if the ability to delve into the system, come up with a better mousetrap is what you are after - go for it. Also have a good escape plan such as reverting back to the original.

Never know if one of these projects will ever come to fruition, but it's fun to learn new information and work on projects that interest you.

Cheers
Word to the wise since its easily overlooked at least on the CX500TC the fuel injectors are low impedance and run at I think 3a the speeduino requires 15a high impedance ones to operate, I think you can use them you just need to add some resistors, I'm looking at replacing with higher discharge ones anyway.
 

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CX500 Turbo, Suzuki GT750 fuel injected triple special, Triumph Tiger 1200, Beta 300RR
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This is a really interesting thread. I have just converted an old Suzuki GT750 2 stroke triple to fuel injection using a speeduino (don't ask!).

My next task is to convert my CX500 Turbo over as well. I am at the start of this but luckily I have an electronics background so I'm not too scared about sensors/injectors. Where to start with the various Maps will be the challenge.

Please keep me posted on how your project is going and what sensor setup you end up with.
 

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This is a really interesting thread. I have just converted an old Suzuki GT750 2 stroke triple to fuel injection using a speeduino (don't ask!).
I know that basicly all these open systems are designed for the car market with simple 4 inline or V8 with even spaced ingnition en injection timings. A three cylinder, 120 degree injection system will be a challenge. A 4 stroke uneven injection / ignition timing will be challenge in it's own.....


Where to start with the various Maps will be the challenge.
If you can do the electronics side of the equation , I will provide you with the Various Maps ( chip-tuning-removing-boost-limit )
 

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That's great news. I am pretty happy with the Speeduino use and setup and interfacing sensors wont be a big issue. I have only just got my CX so need to get my head around how the firing order works to decide if the Speeduino can handle it.

Are there any good threads explaining the sequence?
 

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1985 Honda Goldwing Limited Edition - 1995 Honda Goldwing GL1500 SE - 2012 Suzuki V-Strom DL1000
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Discussion Starter · #29 ·
Check out the Speeduino forum - https://speeduino.com/forum/. Lots of good information. The more teeth on the trigger wheel is best, I did query this with the Megasquirt company and the 8 tooth trigger wheel on the '85 Limited Edition will work, but more teeth is better, say 16 or 32. I have the Gr/Gl sensors located on the rear of the right cylinder head. I believe Honda used two sensors to simulate sequential firing and to aid in a quick start. The Speeduino and Megasquirt only require the use of one of these sensors. Other than these two issues, I will be able to use what has been installed by Honda in the CFI system. As I mentioned above, keeping the interrelationship between the electronic dash, travel computer and the ECU will be a challenge.

The injectors are low impedance and can be used with the Speeduino - uses an Arduino, or a Megasquirt unit. I found during my initial research that both units require an injector spec for calibration of the ECU boxes. Found a lot of good information regarding this on the NGW forum.

Another fellow on the NGW forum installed coil on plug (COP) units on his project. Has some good info on his thread. Installation room and where the plugs are on the Gold Wing is different, but it is a good read.

I put together a pin out spreadsheet and compared the Honda ECU to the Speeduino Project Arduino unit, more work to be done to match all the pins. Been a while since I looked at it.
 

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Discussion Starter · #31 ·
May I ask why ? Because if you think that with a Speeduino you can improve the existing ECU ( more power ) I disagree
Agree with Pim. My foray into the ECU world is a just in case scenario. If I could not find a used OEM ECU and wanted to keep my '85 Limited Edition FI bike going, would need to have a replacement. It's also a great learning tool to delve into the intricacies of fuel injection. Would a modern ECU unit such as the Megasquirt, or the Speeduino with an Arduino processor be better, tunability probably.

A faulty ECU can probably be fixed. I have a faulty ECU with a bad 5 VDC circuit, will get into it to discover why and determine if I can fix it. Have a spare good ECU just in case.

The Honda ECU is probably the most robust unit you will have on a motorcycle, even the newer ones. The integration of the sensors, especially the crank and camshaft sensors on the '85 and '86 FI models to achieve the aim, fantastic. I mention my '85 FI model - third generation CFI system, but it started with the first generation on the CX500 turbo.

Good luck going forward.
 

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CX500 Turbo, Suzuki GT750 fuel injected triple special, Triumph Tiger 1200, Beta 300RR
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I don't disagree it isn't about performance. Yes the maps will be a bit easier to fine tune and boost control might be better but the big issue is sensors availability and being able to use modern sensors with better performance, maybe better injectors and of course having a new ECU if the old ones play up eventually. So no not performance really. Like all the old bikes, its just fun to play.

I have a US barn find 500 Turbo I am breathing life back into at the moment. Usual issues, bad fuel pump, bad 7v gauge regulator, seized brakes and a squirrel in the air box! All very fixable. I might use this as a test bed for a ECU. What I am really after is a 650 turbo that is no where near original to make a kick ass cafe racer with new ECU etc. etc. It would be criminal to take a good 650, so the wait (and the fun with the 500) continues......
 

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Discussion Starter · #33 ·
Have been absent for a while. The past few years have been a challenge, but I was able to bring forward some projects I wanted to do on man '85 Gold Wing Limited Edition such as complete engine rebuild, and paint job. Most of my long term projects are complete so it's time to resurrect this project.

Recap - This project is an ECU replacement project using the existing OEM CFI system as installed by the OEM. It uses the OEM wiring harness, sensors, injectors. I will be installing a 14point7 WBO2 sensor - this is the only new component in the system. I bastardized a faulty ECU for the enclosure and enclosure connector. This way I can utilize the existing wiring harness connector and if necessary, revert back to the OEM ECU. The Speeduino will be installed in this enclosure. I have the Speeduino assembled and firmware installed. Will be using a dual wheel, crank and cam sensor. The '85 CFI system has two cam sensors but only one required. It will be an 8/1 dual trigger wheel install - this is what is fitted. Eight tooth crank (Ns) primary trigger wheel, single tooth cam shaft (Gr/Gl) wheel. The crank and cam sensors output an analogue signal that will be converted to a digital signal through a VR conditioner on the Speeduino. The cam sensors are Hall effect but designed to output an analogue signal.

The injectors are low impedance - low-Z, and can be used because of the OEM resistor unit. This resistor unit has a 12 VDC input, through 2 - 3 Ohm resistors to the injectors - one 3 Ohm resistor for two injectors. The 3 Ohm resistors spec out at 3.5 Ohms, the injectors at 2.8 Ohms. Can change to high impedance - high-Z injectors but no need to at this time.

The CLT and IAT sensors can be used. these would be custom configuration that requires three resistance points be found. These should be at 100 deg C, ambient room temp and -10 degree C. Think close will do well. The test procedure for these sensors is the same.

The Speeduino can control the rad fan if so desired; however, it can be left as per OEM design.

The fuel pump requires the ECU to ground the fuel pump relay. Speeduino has a couple of spare grounding points that can be reallocated in Tuner Studio for the fuel pump control.

Ignition - wasted spark, batch, semi-sequential, and sequential are all supported. Will be using wasted spark initially. if the overall performance is good, won't be changing.

The GL1200 4-wire spark igniters can be used.

The ECU diagnostic, dash CFI fault indicator light will not be available, but I'm thinking a piggyback unit to do this function is possible. The travel computer should not be affected.

Have to determine injector timing characteristics.

About all for now. Cheers
 

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This is a really interesting thread. I have just converted an old Suzuki GT750 2 stroke triple to fuel injection using a speeduino (don't ask!).

My next task is to convert my CX500 Turbo over as well. I am at the start of this but luckily I have an electronics background so I'm not too scared about sensors/injectors. Where to start with the various Maps will be the challenge.

Please keep me posted on how your project is going and what sensor setup you end up with.
@MadforitKev, do you have any pics or write up for the Suzuki GT750 (not completely OT)?
 

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After trying to repair 3 CX650 ecu units the last 2 years I must come to the conclusion that I have not the knowledge and the time to repair these.
I kept an eye on the work Rednax was doing with an Speeduino and his Goldwing and come to the conclusion that indeed the Speeduino open source ECU has matured enough.
I will start looking to use a Speeduino for the CX650T. This bike has an even spaced trigger ( 9/1) and ignition modules like the Goldwing
 

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Discussion Starter · #37 ·
Thanks - getting to a point where the fellows on the Speeduino forum are saying it's time to jump off the cliff and go. Thankfully I have some parts coming and have to install a WBO2 sensor that will slow this down. Hoping for success, but this is the first time I've ventured into this type of electronics world.

Pim- noticed with my browsing of this forum that you have programmed and used an Arduino in the past. It is going to be a good fit for you. I'm thinking that you will not be using the same board I am - the v0.4.4, as it is designed and meant to marry up with to the existing OEM wiring - as close as possible that is.

Once I get what I have working well - that is the sentiment of PSIG from the Speeduino forum, thinking a foray into the other boards might be good, and maybe updating the sensors and such. Always need a good project to do.
 

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Discussion Starter · #38 ·
After trying to repair 3 CX650 ecu units the last 2 years I must come to the conclusion that I have not the knowledge and the time to repair these.
I kept an eye on the work Rednax was doing with an Speeduino and his Goldwing and come to the conclusion that indeed the Speeduino open source ECU has matured enough.
I will start looking to use a Speeduino for the CX650T. This bike has an even spaced trigger ( 9/1) and ignition modules like the Goldwing
Pim - question regarding the MAP sensors Honda used. Do you know what the bar rating is? the v0.4.4 board I have has the 2.5 bar MAP sensor installed.

Intend to do as socrace did with his EFI Gold Wing conversion and use 4 equal length vacuum hoses to a collector box and one hose to the MAP sensor. If I use one of the OEM Map sensors, less vacuum hose to route because I will be installing the Speeduino where the OEM ECU is installed.
 

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I would look at installing the blutooth module on Speedy. It is really quite handy for programming rather than bothering with the plug in.

There is also an Andoid app called MSDroid which lets you ride and log files while showing a full ECU dash (IAT, CLT revs etc).

To data I have only EFI'd my old GT750 2 stroke using Speedy Project X but plan to do a CX turbo at some point.
 

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Discussion Starter · #40 ·
Thought about the bluetooth module, good suggestion. Can MSDroid be used on an iPhone? Will read your Project X thread. I'll look for one this weekend. My thread on the Speeduino Forum under User Projects: https://speeduino.com/forum/viewtopic.php?f=19&t=5544. there is an initial thread in the Getting Started section.
 
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