GM HEI: Cheap and Extremely Effective Ignition Upgrade

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Volker_P
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Volker_P » Sat Dec 24, 2011 6:56 am

Moreover all this may nicely be explained by the equations of Maxwell.

From a more practical point of view I hope you get it running soon. :wink:
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forum links to common technical issues

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SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Tue Dec 27, 2011 9:42 pm

Well, I am down to the spark plug wire.

Apparently I bought resistor wire. Am changing back to the stock OEM wire and see if it will bend the right way.

I did not realize it had a copper core with zero Ohms.

Someone was lucky finding the Belden in a local store. No one around here sells by the foot except a Marine Supplier that sells 10' spools.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Fri Dec 30, 2011 7:56 pm

Pinhead, I have to call on you to check your wiring again, at least the schematic you drew on page 3 of this thread.

In your schematic you have 12v from "Ignition Switch" that I assume to mean not the key "ON" Black wire, but from the Run/Stop switch (which would be the black wire with white stripe connected to the Battery Positive terminal of each module,) but then after the "hard connection" going down the 1K resistor you label it as the "Red/Yellow" wire which is the "start button" voltage to the starter solenoid.

Do you mean this? or are you only connecting your constant bias voltage to the black/white wire?

It would make a huge difference. In only using the Black/White stripe wire, the double diodes are allowing both 1.4v of the A/C reluctor signal (1ms burst) circuit back through ground as well as a constant bleed of .012 amps D/C @ 1.4v to the negative reluctor terminal and "hence" to ground, which I would think would affect your charging circuit seeing a slightly higher voltage than what you are actually producing through your generator alone.

sicj's following schematic also has the "constant" from black/white, not from red/yellow starter BUTTON.

If you are actually tying the Red/Yellow wire into the circuit, then you could be inadvertently adding a start button only boost of the 1.4V D/C to the signal just like what is recommended for the 4 prong, then afterwards when the bike starts, it is reverting to having a 1.4V bias A/C to keep the bike running, but there is 1/1000th of the A/C signal current traveling back to the starter solenoid switch. (0.15 amps @ 150v spike)

Do you have the black/white wire tied to the red/yellow wire? I would think this would be nearly impossible because your solenoid would always be "on" turning the starter motor.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Fri Dec 30, 2011 9:11 pm

Because Lou's original hypothetical diagram for a real world CB 650, I was bleeding off .7v D/C x 2 to ground backwards through the reluctor coil through each module, which really killed my starting voltage because the headlight switch cannot be put into the "N" position. The path of least resistance says that my 425ohm reluctor coil with 10.95v D/C applied and a 10k Ohm resistor coupling the W and G (or P and N) internally, I am bleeding off .025 amps D/C to ground and only biasing the W terminal with .671 volts.

Can we achieve a better result by purposely biasing either W or G with two diodes to ground to control the A/C signal and not use any resistors?

In theory, then, each module would have two diodes from the positive reluctor BEFORE W or P(ositive). OR two diodes FROM G or N(egative) to ground, starting voltage and amperage through a .7 diode. Do we need a Zener Diode from signal?

Could this sufficiently affect the A/C waveform spike pattern?

Or do we need one diode between W to stop reverse voltage, and add a measured .7volts A/C to the input, and then couple the two circuits through adding .7volts D/C (and a substantial amount of amperage) to the G N(egative) terminal?
Buy New, Wire Right. BNWR. LOL

Pinhead
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Pinhead » Sat Dec 31, 2011 2:44 am

SchoolDaGeek wrote:Pinhead, I have to call on you to check your wiring again, at least the schematic you drew on page 3 of this thread.

In your schematic you have 12v from "Ignition Switch" that I assume to mean not the key "ON" Black wire, but from the Run/Stop switch (which would be the black wire with white stripe connected to the Battery Positive terminal of each module,) but then after the "hard connection" going down the 1K resistor you label it as the "Red/Yellow" wire which is the "start button" voltage to the starter solenoid.

Do you mean this? or are you only connecting your constant bias voltage to the black/white wire?


I didn't even realize there was a "yellow/red" label in that diagram (you can ignore it). The "12v from Ignition Switch" is any wire that can source battery voltage when the coils/modules/ignition is "on" and engaged (key ON and kill switch in the RUN position). I'm fairly certain the black/white wire but I could be mistaken (my wires are all faded and dirty). I'd test it with a volt meter to verify.

SchoolDaGeek wrote:It would make a huge difference. In only using the Black/White stripe wire, the double diodes are allowing both 1.4v of the A/C reluctor signal (1ms burst) circuit back through ground as well as a constant bleed of .012 amps D/C @ 1.4v to the negative reluctor terminal and "hence" to ground, which I would think would affect your charging circuit seeing a slightly higher voltage than what you are actually producing through your generator alone.


The bias circuit, if installed correctly, doesn't draw enough power to be of any significance (assuming a 1k or higher resistor is used). Since the "other end" of the reluctor attaches to the module, and is therefore isolated from the rest of the system, there is virtually no current or voltage seen by the electrical system to effect charging.

SchoolDaGeek wrote:sicj's following schematic also has the "constant" from black/white, not from red/yellow starter BUTTON.

If you are actually tying the Red/Yellow wire into the circuit, then you could be inadvertently adding a start button only boost of the 1.4V D/C to the signal just like what is recommended for the 4 prong, then afterwards when the bike starts, it is reverting to having a 1.4V bias A/C to keep the bike running, but there is 1/1000th of the A/C signal current traveling back to the starter solenoid switch. (0.15 amps @ 150v spike)


Nope, not using the red/yellow.

SchoolDaGeek wrote:Do you have the black/white wire tied to the red/yellow wire? I would think this would be nearly impossible because your solenoid would always be "on" turning the starter motor.


You would be correct, and no, I don't. :)

SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sat Dec 31, 2011 1:09 pm

Ok thanks for clarifying.

Today will be my last attempt until spring. We are supposed to get 6+ inches of snow starting tomorrow through Tuesday. I have no garage so if I can't figure it out today I am calling it quits.

I know I still have two variables to change, maybe three. The bike was "galloping" along with the starter yesterday, but as soon as I lifted my thumb from the start button she would die. I have a 39W 1 Watt resistor with a male/female break where I can put in a 1K 5 watt resistor and/or a 2K pot, so I am able to range anywhere from 39 ohms to as high as 3039W. I think I am going to also make a pigtail with my last 3.9K Ohm resistor as well to go back up as high as 3.939, with two diodes in each direction (four total) to the reluctor pickups.

The bike at present has the original plug wires stretched to their limits (#2 and #4) , so I am going to have to check voltage too in case they are not transmitting the spark, or are tilting one of the coils where it is not getting 12v through the spade plug.
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Sat Dec 31, 2011 6:46 pm

Nope. Nothing I tried today worked. I heard a couple of rightly timed combustions a couple of seconds in on two different tries, but the bike would not continue. Also this time the heatsink really heated up to the point of being too hot to even touch, and voltage on W/G climbed to over 6 volts for some reason, even with the double diodes which should have only allowed 1.4 volts max, so I will have to have the modules checked out at Autozone. This phenomena is is Lou's notes but I don't understand what is going on with positive DC feedback.

I am calling it quits until spring. I will check back here from time to time to see if there is anyone who has figured out what the problem is on the 4 prong modules, and can describe accurately their wiring with GM coils on a 81' CB650C.
Buy New, Wire Right. BNWR. LOL

Deepseamdv
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Deepseamdv » Thu Jan 05, 2012 10:33 pm

Help! I've been following this topic and have read all of it more than once. I installed the mods on a 1981 CB-650 using 4 pin modules with the start boost circuit. I get a very week spark on #2 & 3 only, 1 & 4 are completely dead. The reluctors (pulsers, pulse generators, triggers) read 541 & 518 (1&4,2&3 resp.) on a 200 scale. The wiring schematic does not match the text. Yotetalker says the blue wire(1,4 coil (-)) goes to G, the dwg has it going to C, he also says that blue/yellow tube goes to C, the dwg shows it going to G. All other connections agree.
I started with all new parts, C849 coils & DR-100 modules. This is my only transportation and need it running soon.
Any help will be greatly appreciated.
Thanks

Pinhead
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Pinhead » Thu Jan 05, 2012 11:10 pm

I recommend ignoring wire colors completely, as they're probably faded and difficult to discern.

A multimeter is your best friend. Measure out every connection to determine what wire goes to what component and take plenty of notes. Draw yourself a diagram if it helps (that's what I had to do).

Unfortunately I don't have any 4-pin modules and my bike is half-way across the state so I can't pick up a set to test (otherwise I'd be able to help out a lot more with this thread). I was only able to find 7-pin modules at the junk yard so that's what I had to use.

SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Fri Jan 06, 2012 12:20 am

I am sorry you are in this situation. Did you only remove your modules or did you cut the wires in half? Where are you tying into the schematic?

The correct wiring for the Coil wires are to C. The correct wiring for the reluctor negative (Ground) pickups are terminal G. White tubes represent Negative reluctor signal (Ground) white wires to the module, G. (But they change to complete white, the positive signal changes to blue after the battery box harness)

The Ignition below the modules has a Blue side that represents 1,4 with module. This carries all the way through the ignition after the harness connector.

The Yellow side is for the 2,3 module. This carries through as well except inside the battery area, the harness to the modules changes this yellow sleeved blue wire to straight yellow, and the yellow wire it leaves alone. So where i have in the past thought that the two modules were cyclical with each other, it is only a simple wire color change from the bike to the MPS-200 modules, where yellow module wires are to coils and blue is to reluctor positive pickups. It is silly and then there is an additional difference I mention below:

Image

So If you haven't cut them too short or can switch, try the 1,2 and 3,4 instead of 1,4 and 2,3.

If you were prudent and only removed your modules or cut the harness in half, there is an easy way to go back to stock ignition if this is your only means of transportation.

Otherwise if your dilemma means you have more money than time, I would revert to repurchasing the 7 pin modules and appropriate resistor/diode combo and re-wire again to a KNOWN RUNNING VERSION which is Pinheads.

If you take your 4 prong modules back to where you purchased them and they test good, you could refund them and purchase 7 pins. Otherwise you might be out $50 to change to 7 pin modules if you have to have this bike running...
Buy New, Wire Right. BNWR. LOL

SchoolDaGeek
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby SchoolDaGeek » Fri Jan 06, 2012 3:09 am

This information can really only be verified by someone who has held the crankshaft in their hands or can produce a good picture. Is it:

4...................1
....\ -3 - 2 - /

OR
........../ 2 - 1
4 - 3 /

??

My 81 Suzuki GS750E was 1,3 and 2,4.
Buy New, Wire Right. BNWR. LOL

Pinhead
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Pinhead » Fri Jan 06, 2012 3:30 am

SchoolDaGeek wrote:The Ignition below the modules has a Blue side that represents 1,4 with module. This carries all the way through the ignition after the harness connector.


Why do you have the 525-550 ohm resistors in series with the reluctors? Or am I misreading your diagram?

onepieceatatime
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby onepieceatatime » Fri Jan 06, 2012 3:32 am

I'll take a pic of one of the 2 cranks I have sitting out when I get home. I dont remember what they are setup like.
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

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Volker_P
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby Volker_P » Fri Jan 06, 2012 7:30 am

In fact 530Ohms is the ohm resistor reading of the stock reluctors.
So I guess these are just the measured values.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

onepieceatatime
Posts: 323
Joined: Wed Nov 02, 2011 5:12 am
Location: Franklin County, Pennsylvania, USA

Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby onepieceatatime » Fri Jan 06, 2012 7:42 am

SchoolDaGeek wrote:This information can really only be verified by someone who has held the crankshaft in their hands or can produce a good picture. Is it:

4...................1
....\ -3 - 2 - /

OR
........../ 2 - 1
4 - 3 /

??

My 81 Suzuki GS750E was 1,3 and 2,4.



from one of my 1980 CB650 engines.
http://imgur.com/a/uEnOy#12
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE


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