Author Topic: cb650 no spark - ideas?  (Read 2192 times)

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Offline mono

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cb650 no spark - ideas?
« on: August 28, 2014, 01:37:36 PM »
I recently picked up a 1980 cb650K project --- but I'm not really familiar with their ignition systems.

All wires seem connected correctly via the wiring diagram, but I'm not getting ANY spark.

- New plugs/wires (5ohm resistor caps, non-resistor plugs)
- tried 2 sets of coils, no luck.  coils have ground wire attached.
- checked gap on pulse generator - it's very close but not touching.
- tried different spark units from a 750, no luck.

starter motor works, but she just won't spark.  the battery is kind of old but works on my 550, so I'm assuming it's putting out enough juice to fire the 650 up.

any ideas welcome.  I'm going to go double-check all my fuses, but they were OK last time I looked.

thanks,
   mono
« Last Edit: August 28, 2014, 01:42:33 PM by mono »

Offline cb650

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Re: cb650 no spark - ideas?
« Reply #1 on: August 28, 2014, 02:38:26 PM »
kill switch or a short in that part of the wiring?   all the lights work?  It does need a good battery.
18 grand and 18 miles dont make you a biker

Offline mono

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Re: cb650 no spark - ideas?
« Reply #2 on: August 28, 2014, 04:03:39 PM »
yeah, lights are all good, but the kill switch is a good idea as the culprit...   I'll take it apart and see what's up.

Offline mono

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Re: cb650 no spark - ideas?
« Reply #3 on: August 28, 2014, 04:40:30 PM »
OK so the kill switch is fine, and while checking again for spark with the #4 plug out, I got zapped pretty good, so I know that it's getting current.  however, not enough current to apparently create a spark....

anyone have any ideas?

Offline cb650

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Re: cb650 no spark - ideas?
« Reply #4 on: August 29, 2014, 05:52:50 AM »
If you got zapped it must be making spark somewhere.  Maybe wrong caps/plugs.
18 grand and 18 miles dont make you a biker

Offline mono

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Re: cb650 no spark - ideas?
« Reply #5 on: August 29, 2014, 07:24:49 AM »
They're NGK 5k resistor plug caps with NGK D8EA plugs

Offline mono

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Re: cb650 no spark - ideas?
« Reply #6 on: August 29, 2014, 08:38:43 AM »
Figured it out - I didn't realize that you need to hold the plug against the engine block for the spark to jump in the plug.  It's firing!  Thanks for the ideas, guys.  Novice mistake, but I've never really had spark probs before.