Author Topic: Replacing main 8-pin plug when the wire is too short: CB750 K5  (Read 975 times)

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Offline Tugboat

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Replacing main 8-pin plug when the wire is too short: CB750 K5
« on: September 19, 2020, 11:13:30 AM »
My old 8-pin plug from my alternator on my CB750 was falling apart, so I replaced it; but now the wire is too short. Was having a great ride yesterday when the ignition started acting all weird and I can see that the yellow, white & light green/red wires have all pulled out. So what's the proper fix here? Cut the whole thing off and solder new, longer wires to the old? I looked in the Tips section but didn't see anything...
If it's worth doing, it's worth doing twice.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Replacing main 8-pin plug when the wire is too short: CB750 K5
« Reply #1 on: September 19, 2020, 12:10:13 PM »
Did you bend out the tangs on each connector before putting in the new connector plug? If the wires worked with your older one, depending on what all you did, they should work with the new one. Any wire cutting/shortening yet?
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Offline Tugboat

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Re: Replacing main 8-pin plug when the wire is too short: CB750 K5
« Reply #2 on: September 19, 2020, 12:19:23 PM »
I cut the old spades and female bits off to install new. That made the whole thing ~1” shorter, and it’s too tight behind the air box. Wires pulled out of new spades, which are still in the plug.
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Online newday777

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Re: Replacing main 8-pin plug when the wire is too short: CB750 K5
« Reply #3 on: September 19, 2020, 01:07:12 PM »
I cut the old spades and female bits off to install new. That made the whole thing ~1” shorter, and it’s too tight behind the air box. Wires pulled out of new spades, which are still in the plug.


That did make it too short for sure. If you can't change the routing to give the extra length then yes you'll have to splice in wire to make it correct.
Stu
Honda Parts manager in the mid 1970s Nashua Honda
My current rides
1975 K5 Planet Blue my summer ride, it was a friend's bike I worked with at the Honda shop in 76, lots of fun to be on it again
1976 K6 Anteres Red rebuilding project, was originally my brother's that I set up from the crate, it'll breath again soon!
Project 750s, 2 K4, 2 K6, 1 K8
2008 GL1800 my daily ride and cross country runner

Prior bikes....
1972 Suzuki GT380 I had charge of it for a year in 1973 while my friend was deployed and learned to love street riding....
New CB450 K7 after my friend returned...
New CB750 K5 Planet Blue, demise by ex cousin in law at 9,000 miles...
New CB750 K6 Anteres Red, to replace the totaled K5, I sold this K6 at 45k in 1983, I had heavily modified it, many great memories on it and have missed it greatly.....
1983 GL1100A, 1999 GL1500 SE, 1999 GL1500A

Offline madmtnmotors

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Re: Replacing main 8-pin plug when the wire is too short: CB750 K5
« Reply #4 on: September 19, 2020, 02:09:25 PM »
A new alternator sub harness can be had pretty cheap:

https://4into1.com/alternator-wire-harness-31110-300-154-cb750-1969-1978/

https://www.amazon.com/Alternator-Wire-Harness-31110-300-154-1969-1978/dp/B01N52EMO8

I know hindsight is 20/20, but I always cut the old connectors right at the connector to keep the loss of length to within a 1/4". The sub harness linked above is rather inexpensive, but I've never used one so I can't vouch for quality.
TAMTF...


Wilbur



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Offline PeWe

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Re: Replacing main 8-pin plug when the wire is too short: CB750 K5
« Reply #5 on: September 20, 2020, 12:09:16 AM »
Both my bikes have got new harness, but from Yamiya.
Maybe same...

New harness to oil pressure sensor too, the old had really hsrd plastic cover over sensor.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
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