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wiring spagetti

rbeesley1

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ok; i think i must be close but just a few issues left. 1972 cb 750

should there be power to the rectifier combo when the key is OFF?

all lights are finally working as they should but i have NO SPARK!!
continuity thru the coils ; pulled 2 opposite plugs and cranked it over with key on but no spark;even tried new plugs just in case .

also; even with the key off i still have power at the RED WIRE at the ignition switch
after market harness ; switch ; rectifier combo...what a nightmare!!!!!!
here are a few pics of the wiring at the rectifier with TWO open unused connectors
103_4537.jpg103_4538.jpg103_4539.jpg103_4540.jpg103_4541.jpg103_4542.jpg
 
Stock harness you will have 12 volts to ignition switch on red wire . That's the feed from battery
You should NOT have any voltage to other parts with KEY in OFF. If stock harness the kill switch is direct contact from KEY SWITCH ON to KILL SWITCH on handlebar to Coils and Ignition trigger or DYNA what ever you have. Best way to go threw it is with a test light or a volt meter. Start from KEY switch and work you way to Handlebar kill then coil and Ignition trigger. Its a separate wire for charging and reg/rec. Also check your fuse box with key on you should have voltage on both sides of fuses.
Hope that helped a little or you can email me direct at DADDYGCYCLES@YAHOO.COM and I will supply my number.
Rich
 
Red/wht. wire to rectifier will be hot 12v.d.c at all times on the 72 wiring print even with key off.
 
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Please Help!!! Im mechanically inclined but not on older bikes.
I have a 82 Cb750 engine on a Honda Odyssey frame with wiring/spark issues. First? Do I need to have the fuse box to get spark to coils/plugs or is fuse box just for lights?
Second? Do I need to have kill switch/ start button for spark?
I have complete wire harness, ignition with key, regulator/rectifier, ×2ignitors, ×2coils.
Do I need all the extras, switches, gauges, fuses etc. for spark or should I have it with what I'm working with. Thanks for any help.
 
Get a wiring schematic for a 82 750 free on line and know how to read it, You still need a starter solenoid, Use the ignition switch You have or use a toggle switch for power on, A momentary contact switch for the starter, You do not need gauges for the engine to run but at least wire up a oil pressure light at the least, The fuses protect all electrical devices and should be used on the ignition modules. I could go on all day but with the wiring print You should be able to get it going. Good luck with the project.
 
Looking at Your print, The battery has to make connection with the spark units black to red at the switch without a switch connection there is no power, You should have +12VDC at the wires that look like white with the black outline at the spark units. Check with a test light or meter. Also check for proper grounds back to the engine.
 
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