Author Topic: Electrical panel missing component? Starter motor safety unit  (Read 642 times)

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Offline denward17

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Electrical panel missing component? Starter motor safety unit
« on: January 31, 2024, 07:34:27 AM »
A previous owner appeared to have cut 2 wires near the electrics base panel, G/R and LG/R.

Tracing the wire diagrams it appears the G/R goes to the clutch switch, the LG/R goes to the neutral lamp indicator.

Where do these wires connect at the electrics panel?

76 CB550K

Offline bryanj

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #1 on: January 31, 2024, 08:59:41 AM »
To the starter safety interlock circuit or diode
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Offline denward17

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #2 on: January 31, 2024, 10:27:27 AM »
Thanks Bryan, it appears that part was taken off the bike.  It is anchored at the top right of picture in that stay that has nothing in it.

I got a diode ordered, Thanks again.

Offline grcamna2

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #3 on: January 31, 2024, 10:51:05 AM »
Den,those wires/plug go to your silicone rectifier and your bike needs it to charge.
« Last Edit: January 31, 2024, 11:05:00 AM by grcamna2 »
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Offline denward17

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #4 on: January 31, 2024, 12:45:00 PM »
^Thanks Bill, does it matter which wire goes to + or -  ?

Offline scottly

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #5 on: January 31, 2024, 12:58:20 PM »
Den,those wires/plug go to your silicone rectifier and your bike needs it to charge.
Wrong! The diode replaces the older Starter Motor Safety Unit, which prevents the electric starter from operating unless the trans is in neutral or the clutch lever is pulled in; it has nothing to do with the charging system.
Den, it does matter which wire goes where.
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Offline grcamna2

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #6 on: January 31, 2024, 01:46:50 PM »
Ooops  :o  I stand corrected.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
Do your BEST...nobody can take that away from you.

Offline scottly

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #7 on: January 31, 2024, 07:32:54 PM »
^Thanks Bill, does it matter which wire goes to + or -  ?
The light green/red wire goes to the + side of the diode (the arrow on the diode symbol points to it), and the green/red wire goes to the - side. If you get it wrong, nothing bad like smoke and fire will happen, it just won't work as designed. ;)
Don't fix it if it ain't broke!
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Offline denward17

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #8 on: January 31, 2024, 07:37:39 PM »
Thanks Scottly!

I did find a '76 wiring harness on Ebay for $30, so I jumped on it.  I know I could probably find the connector somewhere like vintage connections, but like the idea of having a spare wiring harness anyway.

Offline denward17

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #9 on: February 03, 2024, 06:57:38 AM »
Ebay deal fell through, seller indicated this one was damaged by fire.

Offline MauiK3

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #10 on: February 03, 2024, 07:00:20 AM »
I got some vintage connectors to use when needed, very handy
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Offline denward17

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #11 on: February 03, 2024, 07:02:00 AM »
I got some vintage connectors to use when needed, very handy

I got a few spares as well, hoping I have a couple to fit the diode when it gets here.....

Offline kerryb

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #12 on: February 05, 2024, 10:58:06 AM »
I bought a generic diode from spark moto and attached it to those two wires, works good.
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Offline denward17

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #13 on: February 05, 2024, 11:05:14 AM »
Thanks!
Hoping the one I connected will work, will find out in a few months...

Online Deltarider

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Re: Electrical panel missing component? Starter motor safety unit
« Reply #14 on: February 06, 2024, 12:08:48 AM »
Did any of you complete this safety idea by adding a forgotten lowered sidestand in the scheme? How would that wiring look like?
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