Author Topic: 81 cb650 no spark or start  (Read 3887 times)

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Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #25 on: August 09, 2019, 04:15:10 pm »
No bike won't start it's with the key on OK I'll replace the spark units

Offline DaveBarbier

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Re: 81 cb650 no spark or start
« Reply #26 on: August 09, 2019, 05:46:05 pm »
Oh right, sorry. Then yeah, that voltage is probably ok. But you should measure the battery and then the coils and note the difference. Should be less than a volt difference. More like .3 volts.

Keep us posted on the spark units.

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #27 on: August 18, 2019, 08:09:59 am »
Well... Replaced spark units... No spark... IDK Wat else to do other than sell the bike or take to a bike shop... I'm getting fed up and feel defeated by the bike....

Offline DaveBarbier

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Re: 81 cb650 no spark or start
« Reply #28 on: August 18, 2019, 08:36:39 am »
Did you ever test if the spark units were getting power? I know you checked coils, at least I think I remember you checked if coils were getting power...

And again, no plugs are sparking, correct?

Have you tested the plug caps and/or replaced the plugs with new?

Why don’t you take the tank and ignition cover off and take clear well lit pictures of everything. Spark units too and battery and ground and such.

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #29 on: August 18, 2019, 09:26:48 am »
Put new spark units on new plugs checked ignition coils how do u check plug caps and maybe wires?

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #30 on: August 18, 2019, 09:36:48 am »
I have NFL plugs and caps

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #31 on: August 18, 2019, 10:17:48 am »
Ngk stupid auto correct

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #32 on: August 18, 2019, 10:26:50 am »
But I doubt all 4 of the caps would go bad at the same time... I'm gonna buy new coils wires and caps

Offline jgger

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Re: 81 cb650 no spark or start
« Reply #33 on: August 18, 2019, 10:33:17 am »
Might be a stupid suggestion,  but have you gone over the kill switch and its wiring? For 2 sets of spark units to not work at the same time seems weird to me. It is like something is grounding out.
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #34 on: August 18, 2019, 03:05:23 pm »
There's a cheap Amazon ignition switch on it could that be it


Offline jgger

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Re: 81 cb650 no spark or start
« Reply #35 on: August 18, 2019, 03:22:47 pm »
Maybe, try to hot wire it or bypass the switch.
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline DaveBarbier

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Re: 81 cb650 no spark or start
« Reply #36 on: August 19, 2019, 04:52:55 am »
Possibly, but you said you have power to the coils so your black wire in your harness is energized.

I agree that all plug caps are unlikely the culprit. You can test the plugs and wires. I wouldn’t really replace them if they test good but I could be convinced.

To test the caps I would unscrew them from the wires and stick your multimeter leads in each end on ohms. Should be about 5k if they’re 5k ohm caps, which they should be. For the wires, stick your leads in 1&4 thusly:
  I don’t know what readings you should get for the 650, these numbers are for the 550. Should be somewhat similar and 2&3 should be about the same.

But again, please answer this question. Have  you tested if the spark units are getting 12 volts?

Lastly, are you sure your kill switch is set to RUN? Test that you’re getting 12 volts to the kill switch and out from the kill switch. I’m guessing yes, because you said you are getting 12 volts at the coils, but I want to be sure.

Also, post PICTURES! I want to see your multimeter at the spark units, coils and kill switch showing 12 volts.

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #37 on: August 19, 2019, 06:23:39 am »
 OK I'll post pics black and yellow wire on the coils and spark unit? Also how do I test switch... I don't have a switch anynore it's a a like a car ignition switch and a push button start

Offline DaveBarbier

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Re: 81 cb650 no spark or start
« Reply #38 on: August 19, 2019, 06:57:36 am »
Have you ever had spark since you removed the killswitch? So you have a key you urn to ON and then you have a momentary switch to start the motor? How do you kill the motor?

Black wire on coils with red lead (I think it’s a black and white striped wire actually) and ground with the other lead.

Same for the spark units.

Is the key ignition switch the factory one?

Offline Bjones89

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Re: 81 cb650 no spark or start
« Reply #39 on: August 19, 2019, 01:48:47 pm »
It's like a car turn to off to kill motor turn to on and hit starter button both are located on the electronics box