Topic: Ignition Upgrade using GM HEI Modules

[dave500]

bosch bim024 is reluctor triggered it picks up the ac pulse,another good module is the bosch bim137 that requires a hall effect to trigger it,both will fire low impedence coils and have dwell adjusted in the unit,youll need to use mech advance though.

[Pinhead]

TTT

[kevinharaldcross]

Hey, first time posting. This thread is why I joined the forum, actually.

Are all the wires I need for this to work (save for the 12V from battery) at the plugs where the original igniters were? If so, can I wire everything through the igniter plug and plug in through the harness?

It'd be really helpful to see some more pictures of people's set ups with this system. I know next to nothing about wiring.

[Don R]

 It's not plug and play. There are drawbacks, did you read it all?

[kevinharaldcross]

It's not plug and play. There are drawbacks, did you read it all?

I've spent the last three weeks reading this post and the sister post on the CB650 forum. I've studied the wiring diagram and I get which wires go where from the female connectors the igniters were hooked up to. I just don't understand exactly how I hook the GM modules up to this (and also how how the coils hook up to the two wires the originals were hooked up to).

On my '80 CB650 I have two 5-pin female connectors by the battery:
GREEN: to rectifier
YELLOW/BLUE: to pulse generator
BLACK/WHITE: to engine on/off
YELLOW: to coil
YELLOW/WHITE: to pulse generator

GREEN: to rectifier
BLUE: to pulse generator
BLACK/WHITE: to engine on/off
BLUE/YELLOW: to coil
BLUE/WHITE: to pulse generator

I gathered this from the wiring diagram here: http://www.classiccycles.org/media//DIR_1478304/DIR_1482804/7fd55fff1a102ee5ffff8262ffffe415.pdf

Which of these are the 1,4 and 2,3 +/- pickup wires? The red/yellow shown for the start relay is just next to the battery, correct?

Sorry for sounding like a totally newb but... I am.  Just trying to get this thing running.

[SoyBoySigh]

Sure would be a cool mod to fit the DOHC type pick-up plate and mechanical advance onto the SOHC 750 - but then they're on opposite sides of the crank and hence run in opposite directions. I dunno whether this would matter or not ha-ha. But yeah I sure loved no longer messing around with points. Much as points are a very cool hands-on "Old's Cool" technology and hence a decent learning tool.

All I know is my DOHC "CB900K0 Bol Bomber" is getting "the GM coils mod" as is famous on the DOHC 'F-orum, and the "KZ440LOL" has to swap to the later year magnetic pick-ups rather than the earlier coils.

The only caveat to THAT, is that the later year 440 with the electronic ignition was few & far between compared to how many KZ400's that were made & which remain on the road. You'd THINK that so few are still rolling that there ought to be enough late ignition systems for everybody, but even so - people who have 'em for sale seem to think they're worth their weight in sperm whale puke....

Gotta keep pluggin' away at eBay to see if I can get a good unit for cheap!

Meanwhile, the DOHC Honda series had these units across the entire range. I suppose if the SOHC models were able to utilize the DOHC pick-ups, the same #$%*uation would exist with the Honda four ignitions as is the case with the KZ twin ignitions.

As a DOHC aficionado, this leads me to proclaim "Viva La Difference!" ha-ha.

-Sigh.

[maschinenbau]

Hey all, I just joined this forum to say I've successful made my '79 CB650 run using Cavalier coils and 2 HEI modules. I bought 2 coils for a 2.2L pushrod Cavalier and 2 generic HEI modules. The stock location for the coils is just under the fuel tank, but these are much bigger and won't fit.



This bracket came with the coils and has threads for the mountint bolts. I also want it to secure the battery from moving around.



Nice battery-sized notch.



Coils will hang off the under-seat tray, powered from above by wires and HEI housed inside the tray. I had to cut the connectors off the OEM ignitor units so this system plugs right into the stock harness.





It all mostly fits. Some generic Rockauto spark plug wires complete the kit.



Barely even noticeable. Might need a shield or something to keep the coils dry from the tire.





I'm happy to say it fired right up! Of course the carbs have sprung a leak at the fuel tube that connects #1 and #2, so the rack needs to come back off. Charging system is still not functioning whatsoever, but it should at least be rideable this weekend (for a short while).

[DaveBarbier]

Cool, thanks for the post and pictures. We 650 guys don’t have many options. Would you recommend this mod if your stock ignition was toast? How much did you spend on parts?

I modified a Dyna S to work on mine. Easy if you have a lathe. I’m also making Dyna S and maybe Dyna2000 kits if any other 650 owners are interested.

A shield might be a good idea, you’re also flinging water and sand at your pod filters.

[dave500]

well done!

[maschinenbau]

I would recommend it if you pickup coils are still definitely working but you want a stronger spark or your OEM igniters are junk. Those things can be $100 a piece. I spent about $75 total on the 2 coils, 2 HEI's, 4 plug wires, and 4 spark plugs with the normal car-type terminal. I'm gapped to 0.040 now and will probably go higher.

However my bike still runs like crap probably from a carb issue. Lots of a backfiring, popping, won't run without choke, etc so I won't be able to say how awesome the ignition mod is until I fix that.

And of course it's not a CB650 project without a bad rotor and stator, which I definitely have.

[DaveBarbier]

Awesome, thanks for that. Seems like a good option if someone doesn’t mind big ass coils under their seat.

[Deltarider]

I'm gapped to 0.040 now and will probably go higher.

Why?

[maschinenbau]

You could fit them under the tank you if you weld in a new mounting nut on the frame down-tube.

For plug gap, I was just thinking I should use the stock Cavalier gap spec.

[Pinhead]

You could fit them under the tank you if you weld in a new mounting nut on the frame down-tube.

For plug gap, I was just thinking I should use the stock Cavalier gap spec.

I run 0.080" on mine. Tried 0.100" and the plug wires couldn't contain the spark.

[maschinenbau]

Another tip I forgot to mention:

Buy actual Wells DR100 modules! Autozone sells them with warranty, P/N DR100. The cheap Amazon ones I tried first wouldn't rev past 4500 RPM, despite being "interchangeable" with DR100. Reference this write-up on determining which HEI module you have:
http://gpzweb.s3-website-us-east-1.amazonaws.com/Ignition/HeiModules/HeiModules.html

I don't think the coils look that bad. Because of the daylight gap all along the frame triangle, they sorta disappear from view.

[maschinenbau]

I received some questions about the wiring. I followed that write-up loosely but didn't use the resistors and diodes. I just wired them directly in place of the Honda modules. Literally just cut the connector off my dead Honda units and crimped them onto the HEI's. Hope the pictures help. The wire colors should match what you have. You'll be left with the white and green wires, which are just grounds so I joined them. Coils are also direct swap.  You can see the "W" pin was left empty.

[Sunset Fab]

 I know this is old but putting this on my 80 cb650
My Question is to use the GM coils do I need to mount them with the factory mounting plate with the connectors or can I just mount them alone and plug in the two wires?
I already have the modules mounted on an aluminum heat sink
Thanks, Steve

[willbird]

I know this is old but putting this on my 80 cb650
My Question is to use the GM coils do I need to mount them with the factory mounting plate with the connectors or can I just mount them alone and plug in the two wires?
I already have the modules mounted on an aluminum heat sink
Thanks, Steve

What part number GM coil did you purchase ??

[newday777]

I know this is old but putting this on my 80 cb650
My Question is to use the GM coils do I need to mount them with the factory mounting plate with the connectors or can I just mount them alone and plug in the two wires?
I already have the modules mounted on an aluminum heat sink
Thanks, Steve

Choppers mount them in boxes in other places so can you.

[willbird]

Wondering if a coil like this would offer any better mounting options ??

https://www.autozone.com/ignition-tune-up-and-routine-maintenance/ignition-coil/p/duralast-ignition-coil-c1136/223176_0_0

https://contentinfo.autozone.com/znetcs/psb/en_US/2/0/27/c1136_coil_specs.pdf

Bill

[dusterdude]

That will work

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[Sunset Fab]

I know this is old but putting this on my 80 cb650
My Question is to use the GM coils do I need to mount them with the factory mounting plate with the connectors or can I just mount them alone and plug in the two wires?
I already have the modules mounted on an aluminum heat sink
Thanks, Steve

What part number GM coil did you purchase ??

Don't recall the number but the ones for the Cavalier

[dusterdude]

A dodge neon coil will work too

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