Author Topic: CB750 K3F - AKA The Red  (Read 99156 times)

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Offline MoMo

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Re: CB750 K3F - AKA The Red
« Reply #450 on: December 31, 2018, 02:18:01 pm »
Bah...just be sure and let us know if that particular mod has good results.  I remember an old thread where it was discussed and created quite a controversy.



Like how many forum members does it take to tie vent tubes together?

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #451 on: March 01, 2019, 05:54:32 am »

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #452 on: May 08, 2019, 04:18:24 am »
She stopped charging.  I am currently in the slow and painful process of recalling my electrical engineering  education.  ;D

So far it looks like the coil, white wire against the ground has infinite resistance, that ain't right.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #453 on: May 11, 2019, 03:21:27 am »
The coil against the field had about 9 ohms while on the bike.   When I took it off, the same measurement was infinite resistance.  Seems like trouble is in connecting wires.  I took off the tape and inspected and redone connections that seemed suspicious.

Now all checks out.

I also got frustrated with electronic meter and used this antique machine instead.  Yes, it is big and clumsy but it works well.

Online calj737

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Re: CB750 K3F - AKA The Red
« Reply #454 on: May 11, 2019, 04:41:40 am »
this antique machine instead.  Yes, it is big and clumsy but it works well.
Hey! I resemble that remark  >:(
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Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #455 on: May 11, 2019, 07:03:35 am »
this antique machine instead.  Yes, it is big and clumsy but it works well.
Hey! I resemble that remark  >:(

 ;D ;D

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #456 on: May 15, 2019, 03:23:21 am »
She is back on the road and charges as requested.  Makes quite the difference in headlight and turn signals.  ;D

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #457 on: May 15, 2019, 03:08:55 pm »
Good news
'74 "Big Bang" Honda 750K [836].....'71 Honda 750K project.....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #458 on: May 30, 2019, 03:28:16 am »
Knock on wood, she should be fine now as far as charging.

I had my doubts about the stator, but it charged with the jumper cable on regulator.  I took out the rectifier and there was a small piece of insulation missing from the red output wire, I replaced that and it should be it, finally. 

It was several issues:

- stator and coil leads had conductive connection somewhere before the big 8 plug
- one of the coil leads was basically broken
- one of the stator leadconnectors was pretty much rotten off
- output from rectifier had broken insulation


I learned a lot, hopefully all I need to do is to get new gaskets and seal shift cover and alternator for good.

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #459 on: August 21, 2019, 05:15:50 am »
Added case savers.  Dorky, yes, but I can live with that. ;D

Online calj737

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Re: CB750 K3F - AKA The Red
« Reply #460 on: August 21, 2019, 06:13:37 am »
Many years back I took a riding course led by a noted professional rider. Course was street-oriented though we were on a track riding our own bikes. The Instructor had this to say about crash bars and case savers:
They are more likely to get you killed if you lay a bike down because they will bite and pivot the bike end-for-end, throwing you off badly. They will limit your ability to maneuver the bike tightly and heaven forbid your leg gets between the asphalt and the bars because you will lose your leg. Are any of these likelihood’s worth saving a motor from some scrapes?


I found this to be a really keen insight to an accessory I see on many street bikes and always think back to that advice. Sure, on a dual sport or trail bike they make sense. But personally I would never use them on the street.

Just some concerned friendly input.
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"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 edwardmorris

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Re: CB750 K3F - AKA The Red
« Reply #461 on: August 21, 2019, 09:47:56 am »
Many years back I took a riding course led by a noted professional rider. Course was street-oriented though we were on a track riding our own bikes. The Instructor had this to say about crash bars and case savers:
They are more likely to get you killed if you lay a bike down because they will bite and pivot the bike end-for-end, throwing you off badly. They will limit your ability to maneuver the bike tightly and heaven forbid your leg gets between the asphalt and the bars because you will lose your leg. Are any of these likelihood’s worth saving a motor from some scrapes?


I found this to be a really keen insight to an accessory I see on many street bikes and always think back to that advice. Sure, on a dual sport or trail bike they make sense. But personally I would never use them on the street.

Just some concerned friendly input.

Believe it or not, I heard nearly the same thing at the MSF safety course I took few years back and skipped them...

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #462 on: September 11, 2019, 03:03:25 am »
Speedometer died.  It would still count miles but it showed either 0 or off the scale mph.  I found a decent used one on ebay and swapped out the face.  Lost only 2300 miles in count, I can live with that. 

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #463 on: September 21, 2019, 03:30:17 am »
The longest trip Red made so far.  Went to Morgantown to see my son and back - 500 miles in two days - she did well, as I learned to expect from SOHC Honda :)
« Last Edit: September 21, 2019, 03:44:02 am by 70CB750 »

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #464 on: May 09, 2020, 12:22:25 pm »
Red got rebuilt PD carburetors and I took her for a spin.  Holy #$%*, what a difference!  She will rev to 8 000 in second gear and third gear and that's how far I got, she is too fast for my local roads.  No more problem accelerating in 5th.

Still want to get a 78 F air box and reroute throttle cables and figure out an adapter for the petcock, but she is where she was supposed to be.

Not sure, why the previous owner ran her with older carburetors.

Note:  42 idle and 110 main jets

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #465 on: July 29, 2020, 04:19:23 am »
Quite the surprise yesterday.

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #466 on: July 29, 2020, 06:34:48 am »
Did it surprise you when the bike was rolling?!
'74 "Big Bang" Honda 750K [836].....'71 Honda 750K project.....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #467 on: July 29, 2020, 06:37:25 am »
Did it surprise you when the bike was rolling?!

Yes, it was dragging on the chain cover.  I assessed it as safe to get home, it was still holding on the side of the clip.  Never seen it before.

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #468 on: July 29, 2020, 03:51:37 pm »
Did it surprise you when the bike was rolling?!

Yes, it was dragging on the chain cover.  I assessed it as safe to get home, it was still holding on the side of the clip.  Never seen it before.

Sounds like a wild ride!  Have not seen that either, good to hear you made it home.
'74 "Big Bang" Honda 750K [836].....'71 Honda 750K project.....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #469 on: August 22, 2020, 04:19:10 am »
She stopped charging again, the stator showed connectivity against the ground.

I went Edward Morris on it, found NOS stator on the ebay and also bought new connecting pigtail.  I had to replace connectors on the field coil, too.

Anyway, since I was installing brand new pigtail and not 40+ years of fixes and replacements I found out Honda is smart and I am not so smart.  The pigtail folds beautifully into the transmission cover - there is a special slot for it - and after that the chain cover just slides in.


Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #470 on: October 23, 2020, 02:22:21 am »
Significant achievement on 10/22/2020.

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #471 on: November 15, 2020, 12:24:57 pm »
Thats quite a road trip!
'74 "Big Bang" Honda 750K [836].....'71 Honda 750K project.....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #472 on: November 15, 2020, 02:20:44 pm »
Thats quite a road trip!

Quite right - especially since the bike and I are together almost hundred years old  ;D ;D

Offline 70CB750

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Re: CB750 K3F - AKA The Red
« Reply #473 on: December 20, 2020, 02:21:57 am »
Addressing the long overdue fork leak.  It would be open and shut but I could not find my seal set and had to buy a new one. 

Offline Stev-o

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Re: CB750 K3F - AKA The Red
« Reply #474 on: December 21, 2020, 06:05:25 am »
Hate when ya cant find something you know you had!
'74 "Big Bang" Honda 750K [836].....'71 Honda 750K project.....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........