Author Topic: 76 750F start switch repair  (Read 1799 times)

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Offline Chief

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76 750F start switch repair
« on: July 20, 2018, 09:03:06 AM »
Are there any fixes out there for the start button on these bikes short of replacing the entire handlebar switch assembly?  Mine seems to be missing the button.  Has anyone successfully repaired one of these switches? 
76 CB750F Super Sport

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 76 750F start switch repair
« Reply #1 on: July 20, 2018, 12:47:10 PM »
The plastic box is/was 3D printed and available from a member. Others have installed a micro momentary? switch. Otherwise the new controls from Honda have what appears to be a softer and perhaps non brittle plastic box. 
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Chief

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Re: 76 750F start switch repair
« Reply #2 on: July 20, 2018, 02:56:03 PM »
Well Jerry, I am finding out that this is a common issue.  I had hoped that i might be able to repair the switch but it looks like a new switch may be in order.  I do not wish to use the aftermarket switch assembly for fear the wiring harness will be too short.  Do you,or anyone else have any info on the microswitch that could be used?  How about the 3D printed box?
76 CB750F Super Sport

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 76 750F start switch repair
« Reply #3 on: July 20, 2018, 06:19:17 PM »
Well Jerry, I am finding out that this is a common issue.  I had hoped that i might be able to repair the switch but it looks like a new switch may be in order.  I do not wish to use the aftermarket switch assembly for fear the wiring harness will be too short.  Do you,or anyone else have any info on the microswitch that could be used?  How about the 3D printed box?

In all likelihood the wiring may be wrong as I've seen. Gimme a day or 2 to find the replacement box link. No luck yet.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Abud

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Re: 76 750F start switch repair
« Reply #4 on: July 20, 2018, 09:44:18 PM »
I repaired the missing starter button on my 1970 K0 switch assembly. Found a junk switch for a 1975 on ebay. Pulled both apart and replaced starter button. Not to difficult if you are patient and meticulous.  A lot of tiny pieces in there.   I have only bench tested my repair with a continuity light but seems to work fine. $26 repair. And switch assby remains stock to my 70. 

Offline ekpent

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Re: 76 750F start switch repair
« Reply #5 on: July 21, 2018, 04:46:57 AM »
I repaired the missing starter button on my 1970 K0 switch assembly. Found a junk switch for a 1975 on ebay. Pulled both apart and replaced starter button. Not to difficult if you are patient and meticulous.  A lot of tiny pieces in there.   I have only bench tested my repair with a continuity light but seems to work fine. $26 repair. And switch assby remains stock to my 70.
Starter buttons are different on the early K's then the later F's. I have fixed both. Don't forget that if you get the 3-d printed box for the F model your still going to need the tiny ball bearing,spring,metal plate etc. that go with it. If you dissect the old be sure to save those goodies or if its all missing you will need to source it from a scrap unit.

Offline Chief

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Re: 76 750F start switch repair
« Reply #6 on: July 21, 2018, 04:55:47 AM »
Thanks guys. I have not disassembled the old switch as yet so not sure exactly what parts are missing.  I’m sure the button is a goner though.
76 CB750F Super Sport

Offline evinrude7

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Re: 76 750F start switch repair
« Reply #7 on: July 21, 2018, 07:56:58 AM »
Thanks guys. I have not disassembled the old switch as yet so not sure exactly what parts are missing.  I’m sure the button is a goner though.

chief, i have a start button you can have.  if the wiring is the same on your 76F as my 76K?  it's not a stock button but it fits, looks and works perfectly.  i bought a few of them when i placed the order last year. 
cb750 k6 - ugly

Offline Bankerdanny

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Current: '76 CB750F. Previous:  '75 CB550F, 2007 Yamaha Vino 125 Scooter, '75 Harley FXE Superglide, '77 GL1000, '77 CB550k, '68 Suzuki K10 80, '68 Yamaha YR2, '69 BMW R69S, '71 Honda SL175, '02 Royal Enfield Bullet 500, '89 Yamaha FJ1200

Offline Bankerdanny

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Re: 76 750F start switch repair
« Reply #9 on: July 21, 2018, 08:07:30 AM »
But this is just the housing. If you are missing the button you need to find that separately.
"The problem with quotes on the Internet is that you never know if they're true" - Abraham Lincoln

Current: '76 CB750F. Previous:  '75 CB550F, 2007 Yamaha Vino 125 Scooter, '75 Harley FXE Superglide, '77 GL1000, '77 CB550k, '68 Suzuki K10 80, '68 Yamaha YR2, '69 BMW R69S, '71 Honda SL175, '02 Royal Enfield Bullet 500, '89 Yamaha FJ1200

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 76 750F start switch repair
« Reply #10 on: July 21, 2018, 10:21:14 AM »
+1 on Danny's info.

Thanks Danny.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Chief

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Re: 76 750F start switch repair
« Reply #11 on: July 21, 2018, 11:47:43 AM »
evinrude7
you have a PM
76 CB750F Super Sport

Offline evinrude7

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Re: 76 750F start switch repair
« Reply #12 on: July 21, 2018, 03:26:04 PM »
evinrude7
you have a PM

ralph, you have a package in the mail. 
cb750 k6 - ugly

Offline Chief

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Re: 76 750F start switch repair
« Reply #13 on: July 21, 2018, 08:31:52 PM »
Thank you and thanks to all who shared their insight.
76 CB750F Super Sport

Offline ekpent

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Re: 76 750F start switch repair
« Reply #14 on: July 22, 2018, 06:39:31 AM »
Thank you and thanks to all who shared their insight.
One more insight is the fact that model and year had an extra wire in the starter button unlike earler K models that would disable the headlight when the button was pushed to save battery juice and come back on once the button was let go. That will have to be addressed to get your headlight working .

Offline evinrude7

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Re: 76 750F start switch repair
« Reply #15 on: July 22, 2018, 08:44:51 AM »
Thank you and thanks to all who shared their insight.
One more insight is the fact that model and year had an extra wire in the starter button unlike earler K models that would disable the headlight when the button was pushed to save battery juice and come back on once the button was let go. That will have to be addressed to get your headlight working .

should be 3 wires on the 76F correct?
cb750 k6 - ugly

Offline Bankerdanny

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Re: 76 750F start switch repair
« Reply #16 on: July 22, 2018, 09:57:07 PM »
Thank you and thanks to all who shared their insight.
One more insight is the fact that model and year had an extra wire in the starter button unlike earler K models that would disable the headlight when the button was pushed to save battery juice and come back on once the button was let go. That will have to be addressed to get your headlight working .

should be 3 wires on the 76F correct?

Yes, a black wire brings power to the switch. When the button is pushed power goes to the yellow/red wire to the solenoid. When the button is not pushed power goes out through the black/red wire to the fuse block.
"The problem with quotes on the Internet is that you never know if they're true" - Abraham Lincoln

Current: '76 CB750F. Previous:  '75 CB550F, 2007 Yamaha Vino 125 Scooter, '75 Harley FXE Superglide, '77 GL1000, '77 CB550k, '68 Suzuki K10 80, '68 Yamaha YR2, '69 BMW R69S, '71 Honda SL175, '02 Royal Enfield Bullet 500, '89 Yamaha FJ1200

Offline tekkie

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Re: 76 750F start switch repair
« Reply #17 on: July 23, 2018, 10:53:01 AM »
i had the exact same issue i just replaced it with a reproduction from ebay since mine was well aged  and it was surprisingly nice quality