Author Topic: 1973 CB750 Four Coil Issue  (Read 1936 times)

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Offline Bankerdanny

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Re: 1973 CB750 Four Coil Issue
« Reply #25 on: June 05, 2019, 10:17:29 AM »
O.K. The 1 and 4 coil is triggered by the Blue wire from the left hand point set. If you plugged that Blue wire into the Yellow wire to the 2-3 coil and you got spark on 2-3 then the 2-3 points are not operating. Very first thing would be to shine up the 2-3 ( right hand ) points . A points file is best, but who has one of them anymore ! 400 grit paper folded over and worked on the point faces is next best thing. When they are shiny, pass a white business card ( best if soaked in carb cleaner ) thru' the points to remove any grit left by the sandpaper. Start bike. If still no running on 2-3 then it's time to set the points gap on 2-3 as the points may not be opening.

I know for certain that O'Reilly Auto still sells points files.
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Offline Spanner 1

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Re: 1973 CB750 Four Coil Issue
« Reply #26 on: June 11, 2019, 07:58:52 PM »
Good to know Danny !!
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline HondaMan

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Re: 1973 CB750 Four Coil Issue
« Reply #27 on: June 30, 2019, 08:34:16 AM »
Hello,

I contacted 4into1 and they stated, "The points and condensers are a generic branding and are made in Taiwan".  Would this indicate Diachi?

Yep.
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