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Discussion Starter #1
So I finally got my CB450 up and running (albeit rather roughly...)and when I was setting the timing(static with a light bulb), the left side would light up fine, but when I would move the test light wire to the right side, it would not light up at any time in the engine's rotation... Is this likely due to faulty ignition coils? Or is there something else I should check?

Also, the exhaust on the left side is hot, but the right side is rather cool. Any suggestions would be greatly appreciated!
 

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Sensei
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if the light doesn't light up, the points aren't opening and the plug can't fire...
several possibilities: The points are corroded and even when/if they do close they don't make contact, so there is no difference when they open....
The points don't open........
OR they don't close.....
OR....Power never makes it to the points... (grounded somewhere along the wire)
 

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Discussion Starter #3
Thanks for the quick reply! So where are the points receiving power from? Is it directly from the coils or are they hooked up to the battery and then they send signal to the coils? Sorry for my incompetence... ;)

Also, I hooked a timing light up to the left side (the one that IS firing) and the firing was very sporadic (at least at idle). Is this also pointing towards faulty points or ignition coils? The points look relatively clean and shiny, so I don't think corrosion is a problem...
 

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Check the throttle cables under the tank too. One cable may not be seated where they go into the 2 into 1 connector.
 

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Sensei
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Both coils receive power through/from the same black/white stripe wire(from the "kill switch")...... Power travels through the coils to the points where it grounds, completing the circuits....As the points break (open) the inducted surge current travels to the appropriate plug ( to re-establish ground by jumping the plug gap to "vent" the induced energy, creating the spark)....
(this is an over simplification, but a good explaination).....

Allen:... What do the throttle cables have to do with spark, or lack thereof ?.... Please don't confuse the issue....
 

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Discussion Starter #6
Great explanation! I'll try to take a look at the wiring tomorrow to see if there's an issue with the grounding.

Any thoughts on the intermittent strobing for the left side? The strobing would seem fine and then every few seconds it would kinda skip around and then come back to "normal." This could obviously be heard as well as seen...
 

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Sensei
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By "skip around' do you mean the index line wasn't "on index" or the light flash was just intermittant?...The first situation could indicate a problem in the advance unit...The second could be power supply (weak battery).....
 

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66Sprint said:
Allen:... What do the throttle cables have to do with spark, or lack thereof ?.... Please don't confuse the issue....
My bad, wrong post :?
 

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Discussion Starter #9
Well I went and did some more continuity tests today with a multimeter and everything seemed to check out. I also disconnected and then reconnected all of the wires going to and from the points. Somehow, lo and behold, that seemed to do the trick! Bad connection somewhere I guess...

The main issue now is the advance timing seems to be way off on the right cylinder(the timing marks just "disappear" when the engine is reved up passed 3-3.5k or so). Upon closer inspection, I noticed that the right "weight" on the advance mechanism seems to have a small crack (the little piece that juts out and touches/notches in to the center rotor). And it doesn't seem to move as freely as the left side. Guess that means I need a new one... I'm wondering if I should just replace the whole points piece as well (maybe the coils too while I'm at it...).

Thanks again for the help!
 
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