GM HEI: Cheap and Extremely Effective Ignition Upgrade

If it's broken or just needs tweaked

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

Postby Loudhvx » Tue Mar 06, 2012 12:06 am

The primary side of the GM coils will be near zero. Actually somewhere around .4 to .6 ohms.

If you are getting spark from that test, then put everything back the way it should be, then swap the pickup wires at the G teminals. If the problem moves, then one pickup is bad or has a spec different from the other. Double check that both pickups are the same distance away from the tip of the rotor, as well.

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

Postby klougnot » Tue Mar 06, 2012 8:05 am

Loudhvx wrote:The primary side of the GM coils will be near zero. Actually somewhere around .4 to .6 ohms.

If you are getting spark from that test, then put everything back the way it should be, then swap the pickup wires at the G teminals. If the problem moves, then one pickup is bad or has a spec different from the other. Double check that both pickups are the same distance away from the tip of the rotor, as well.


Ok Thanks Lou! The primary is .01 ohms I will try a different ohm meter and report back. It will probably be a couple days through. I will let you know how things progress.

arthurcun1
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby arthurcun1 » Tue Mar 06, 2012 9:54 am

hi, regarding the wells c849 coils can anyone advise me on how to wire them up. the existing coil connectors on my cb 650 consist of 2 wires attaching to two spade connectors on the coils.there does not seem to be any connectors on the wells coil,and which of the existing wires connect where.excuse me for my ignorance but i am a complete dunce as far as electrics are concerned ,i have tried to follow the wiring diagram for the modules and think i have that right ,but i had some confusion as to which lead went where when i found two leads of the same colour.i have been trying to sort this now for two weeks but am afraid of frying the electrics if i get it wrong. art

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

Postby klougnot » Tue Mar 06, 2012 8:05 pm

arthurcun1 wrote:hi, regarding the wells c849 coils can anyone advise me on how to wire them up. the existing coil connectors on my cb 650 consist of 2 wires attaching to two spade connectors on the coils.there does not seem to be any connectors on the wells coil,and which of the existing wires connect where.excuse me for my ignorance but i am a complete dunce as far as electrics are concerned ,i have tried to follow the wiring diagram for the modules and think i have that right ,but i had some confusion as to which lead went where when i found two leads of the same colour.i have been trying to sort this now for two weeks but am afraid of frying the electrics if i get it wrong. art


This is not a direct swap for the CB650 coils. You need to wire up one side of the c849 coil to the black/white switched power wire and the other side goes to the HEI module.

May I ask why you want to use the c849 coils? Are you not getting any spark? Have a hard starting bike? What problem are you trying to solve with this mod. I would start there.

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

Postby facefirst » Tue Mar 06, 2012 9:22 pm

Will this work on a '79 CB650?

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

Postby klougnot » Tue Mar 06, 2012 11:18 pm

Pinhead got it to work on his 79. Check out the entire thread and you will see a video in the first few pages of this thread.

arthurcun1
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby arthurcun1 » Wed Mar 07, 2012 7:03 am

Hi, you asked why i wanted to change the spark units for the wells system .it is because the honda spark units melt and cease to work ,at least mine have ,and they are so expensive to replace. art

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

Postby Volker_P » Wed Mar 07, 2012 7:53 am

Welcome here! :D

the black stuff melting out of the spark units does not necessarily mean they are defective. Try if you still get a spark. In this case one may just refill them, e.g. with JBweld: viewtopic.php?f=4&t=2290&start=11

Did that more than ten years ago, too. For me melting happened together with enhanced charging voltage.
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arthurcun1
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Re: GM HEI: Cheap and Extremely Effective Ignition Upgrade

Postby arthurcun1 » Wed Mar 07, 2012 11:27 am

hi. thanks, it was also bad at starting and i have cut the wires to use on the wells ignition modules,the guy in our local bike shop said its a common fault and a bad system .also if the black and white goes to the new coil i was assuming the other wire allready comes from the spark unit and if so where does it go to if it does not connect to the coil ,what is its function.there is what looks like a fixing hole on the new gm coil is this an electrical connection as there are no other signs of a connection. art

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

Postby klougnot » Wed Mar 07, 2012 6:07 pm

arthurcun1 wrote:hi. thanks, it was also bad at starting and i have cut the wires to use on the wells ignition modules,the guy in our local bike shop said its a common fault and a bad system .also if the black and white goes to the new coil i was assuming the other wire allready comes from the spark unit and if so where does it go to if it does not connect to the coil ,what is its function.there is what looks like a fixing hole on the new gm coil is this an electrical connection as there are no other signs of a connection. art


Art,

I would just read the first few pages of the thread all you need is there. So long as you follow the diagram you will be ok. The thing that trips people up is that the yellow and blue wires with the white tubes need a good frame ground. Do not run without grounding these wires and the HEI units. Start back on page 1 and go from there.

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

Postby Volker_P » Thu Mar 08, 2012 3:06 am

arthurcun1 wrote:the guy in our local bike shop said its a common fault and a bad system.

How old is this guy? I tend to give a damn on the opinion of guys that started to learn their profession after these bikes appeared.

No doubt that a working (!) HEI ignition is superior, however the stock system is neither bad nor very susceptible except the black stuff melting out. I'd say not too bad for Honda's first effort of an electronic ignition on an inline four.
So the stock ignition is in some sense a historic document. :lol:

Starting may be hard in fact. From the ignition point of view, one could try to avoid to have resistive plugs together with resistive caps. That would be about 20kOhm all together for one coil which seems quite much. Nevertheless this will enhance coil lifetime.
Another issue is reasonable carbs synchronisation, a completely closing choke and a well adjusted throttle lifter which is engaged at the very end position of the choke.
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

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

Postby SchoolDaGeek » Sat Mar 10, 2012 4:15 pm

The cowboy in the sunset pic was just for fun. Sorry Geek I just could not help myself.


No offense taken! At least you made fun of something I laughed at as well. To date we have no 4 prong module success on a CB650 that has reported back to the forum. I am still following though and spring will soon be here.

But if you leave one or both plug wires open where a path cannot be found for the discharge, the coil will find a path internally (it is then dead, but may not appear dead to an ohm meter test), or the igniter will find a way to discharge the primary side internally (it is then dead, but may not appear dead to an ohm meter test).


This is new information that cannot be verified through the Wells website:

http://www.wellsve.com/

All the information that is given is that the entire setup, (single module on a distributor and 2-3 coils) should be replaced when the fault is located to either side of the equation. Bad coils can fail a module, and a bad module can fail the coils. But as far as I know, the modules can only be overloaded with greater than 10k of energy, extremely robust, and the coils are somewhere around 22k of voltage/spark.

But Pinhead said that he has had some report that they've gone through three sets of modules before one worked.

I am still waiting for the 4 prong to work on a CB650 and reported back with any updated changes of what was necessary.

As of the spring, my first job is to completely disassemble the inductors down to the crank, clean and lube everything and then dial in the right advance. I was getting spark most of all my tries, but the timing had to be off because the real world bike just would not catch.

Let's say this HEI IGN takes the bike back to 100% or better spark-wise... you need to look at where the signal is starting in the reluctors to make sure that the timing is 100% too, not pulled out through neglect, rust, or the last owner who turned them a few degrees off.
Buy New, Wire Right. BNWR. LOL

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

Postby klougnot » Sun Mar 11, 2012 7:48 am

A little update I found out why I was only getting spark on 1 of the pickups. The problem was that I was tapping into the yellow/red wire off the starter solenoid. I am not sure why, but the voltage was dropping to much to trigger the HEI. By moving 12+ to the left side of the starter solenoid I was able to get enough juice to consistently trigger both pickups. I probably could have spliced into the headlight bucket, but then I would have had to run an extra wire.

Not sure how many degrees goes by from the time the rotor and pickup tip line up and the bike fires. Hopefully not too many as both are lined up at the F mark. I don't think this would be any different from using the stock spark units, but we will see. I know my advance is stamped with 300 degrees and the cb650 says 426 degrees.

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

Postby Volker_P » Sun Mar 11, 2012 7:55 am

klougnot wrote:.... and the cb650 says 426 degrees.

:lol: Great! :lol:

426 is the middle part number of the CB650! I know it is stamped somewhere on the advancer. Would be more than 360°, too!

It's your fault that now I have this carpet taste in my mouth! :lol:
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forum links to common technical issues

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

Postby klougnot » Sun Mar 11, 2012 8:02 am

Thanks Big V another one to add to the knowledge base. Not sure what you mean about the bad tasting carpet not trying to rub your nose in it if that's what you mean. If this thing runs it will be the event of the year. It's not every day a 40 year bike gets a new ignition system.


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