Author Topic: 74 CB750 first Build ignition issue  (Read 1407 times)

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Offline ElNoob88

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74 CB750 first Build ignition issue
« on: April 22, 2019, 01:30:34 pm »
So I bought a 1974 Honda CB750. This is my first bike my first Build. So when I bought it the PO had a wiring nightmare going on. I wired a new harness in. I traced all wires, exchanged the antique Rectifier and Regulator for a new combo one. The safety unit was destroyed so I did the bypass. Then I had no spark on starter solenoid and decided to ground the GR/Rd instead of feeding it power. Bike is on neutral and I keep it on the stand....
Now the starter tries but no ignition. So I wonder if my kill switch is in the way. Kill switch is plugged into coils but there is no power coming from it at all. Should there be voltage on that wire the BLK/Wht.


Thank you thank you

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Offline ElNoob88

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Re: 74 CB750 first Build ignition issue
« Reply #1 on: April 22, 2019, 10:29:10 pm »


So I bought a 1974 Honda CB750. This is my first bike my first Build. So when I bought it the PO had a wiring nightmare going on. I wired a new harness in. I traced all wires, exchanged the antique Rectifier and Regulator

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I figured it out ...

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Offline calj737

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Re: 74 CB750 first Build ignition issue
« Reply #2 on: April 23, 2019, 03:51:00 am »
I hope that you removed 12v power from the Gr/R wire! That’s your Neutral switch wire and is a ground, not powered.

'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline ElNoob88

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Re: 74 CB750 first Build ignition issue
« Reply #3 on: April 23, 2019, 12:11:15 pm »
I was told to remove the switch completely. So it's not connected to the switch on the handle bars. Should I also remove the actual switch in the case??

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Offline calj737

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Re: 74 CB750 first Build ignition issue
« Reply #4 on: April 23, 2019, 01:34:04 pm »
No. And no. You NEED a NEUTRAL switch for safety. Whether you use the clutch safety switch is up to you.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis