Author Topic: Remarkable! An unusual 750K6 rebuild.  (Read 6531 times)

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Offline HondaMan

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Remarkable! An unusual 750K6 rebuild.
« on: October 16, 2015, 08:16:51 PM »
I started a rebuild today for one of our members who have a nice, but high-mileage, 750K6. Here's the point to remember about this bike, before I get into more details: he flew to Michigan (or Minnesota, one of those States up there...) to buy it, then rode it back to home in California (3000 mile trip). On the way, he stopped by here (in Colorado) to talk about this rebuild, and he brought me the bike last week to start on it. He said the bike ran fine, but is fairly high mileage (I'll try to find out that number and post it later).

When I took off the top end of the engine today, I was surprised to find: the oil jets are missing!  :o
The top end has recently had the cam bearings replaced, and the rocker shafts show signs of the high-mileage, so they were re-used despite the new castings being installed. The cam cover was glued down tightly (with copper-laced sealant of some kind) and every screw and nut Loctited but good. The #1 and #4 intake valve guides are quite worn, but no other unusual top-end wear was found - the cam looks to be very young, maybe 5k-10k miles, I'd estimate. Some of the Parkerizing is still evident!

So, as I go through the rest of this engine, I'm going to post the "wear numbers" here that I find. It will be interesting to see how the bottom end fared with NO OIL JETS at all in the top end!

Many years ago, a chopper rider I knew told me that some of his buddies were "making this oil mod" to their 750 top ends. I took it (and him) with a grain of salt, as he was a habitual prevaricator on many topics, but now, I wonder?   :D
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

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Offline oldhatt45

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #1 on: October 17, 2015, 05:16:55 AM »
Sounds like this is going to be a very informative build. 
Will be following this for education!!!!!!

Thanks for doing this Mark.

Charlie

Offline Mushu

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #2 on: October 17, 2015, 02:47:25 PM »
Hi Mark;

Another learner  :)

Philippe M
CB750 K1 owner.

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #3 on: October 17, 2015, 08:16:14 PM »
Hi all. My name is Michael and I'm the owner of the bike that Mark is rebuilding here.
First let me say that I'm soooo happy that Mark agreed to do this build. I purchased the bike from a gentleman in Detroit from a cycle trader add. He owned it for the last 20 years and rode it weekly in the non winter months. He is Japanese and is nearing retirement. At which time he will move back to Japan. He sold the CB in order to buy a newer Harley road king to take with to Japan.
When looking for a CB750 to buy I came across so many scams. Bikes did not exist, adds created with images taken from web sites. To make matters worse when I came across this bike, the seller was also skeptical as he was approached by scam artist that wanted him to ship the bike and trying to pay with fraud PayPal accounts. It took awhile for the seller and I to trust one another. I flew to Detroit, he picked me up from the airport, I loaded my luggage, and started the 2600 mile trip home to California. Rode thru high winds, freezing 40 degree weather, rain and snow I made it home. I don't think I was dry for 5 days. The best part of the trip was meeting Mark when passing thru Denver. The worst part was just a few hours Later  riding thru a snow blizzard in the Rockies. Bike ran find except for battery died after 80 miles. Kick started the rest of the way home.
The bike has 73000 miles.
A picture of the bike in my garage before the restoration.

Offline Stev-o

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #4 on: October 17, 2015, 08:30:08 PM »
Subscribed...bike appears to be in fantastic condition. 
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline dusterdude

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #5 on: October 18, 2015, 11:14:11 AM »
Welcome and she's pretty
mark
1972 k1 750
1949 fl panhead
1 1/2 gl1100 goldwings
1998 cbr600 f3

Offline CycleRanger

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #6 on: October 18, 2015, 11:29:08 AM »
That does look nice. I've never seen the front blinkers mounted like that.
Do you have a copy of the Honda Shop Manual or Parts List for your bike? Get one here:
https://www.honda4fun.com/materiale/documentazione-tecnica
CB750K5        '79 XL250s     CL350K3
CB750K3        '76 XS650      '76 CJ360T

Offline oldhatt45

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #7 on: October 18, 2015, 11:39:27 AM »
Cycle Ranger,

I have a 1976 K6 as well and there are a couple of differences in the front end.
Signal lights mounted more like a 77 or 78 and no fork gaitors, also looks more like a 77 or 78 with the exposed fork uppers.

Would like to se a couple more pictures (full side on shots of both sides and a front and rear view)

But she looks pretty much like a twin to mine, even the paint fade on the tank.  :)  :)  :)

Charlie

Offline CycleRanger

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #8 on: October 18, 2015, 12:13:36 PM »
Cycle Ranger,

I have a 1976 K6 as well and there are a couple of differences in the front end.
Signal lights mounted more like a 77 or 78 and no fork gaiters, also looks more like a 77 or 78 with the exposed fork uppers.

Would like to see a couple more pictures (full side on shots of both sides and a front and rear view)

But she looks pretty much like a twin to mine, even the paint fade on the tank.  :) :) :)

Charlie

Huh, I have never seen a stock '76 K like that. Never in person or a photo.
« Last Edit: October 20, 2015, 08:46:35 AM by CycleRanger »
Do you have a copy of the Honda Shop Manual or Parts List for your bike? Get one here:
https://www.honda4fun.com/materiale/documentazione-tecnica
CB750K5        '79 XL250s     CL350K3
CB750K3        '76 XS650      '76 CJ360T

Offline oldhatt45

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #9 on: October 18, 2015, 12:35:30 PM »
CycleRanger,

Only way we'd know is via information on the VIN Tag.  It gives the month and year of Manufacture.

It could be that the original owner changed out those parts after seeing a 77 or 78???????

I'm pretty sure they were not stock either on K6's.

Charlie

Offline andy750

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #10 on: October 18, 2015, 01:53:00 PM »
Great story and great looking bike. I wouldnt worry about the 73K on the clock as its been well taken care of. Mine now has 86k on the clock (K4) and had a top end engine refresh at 60K and it runs amazing! I do take good care of it so if you have that then you have many good miles ahead of you. Riding from Detroit to Denver is a great start ;)

Good luck
Andy
Current bikes
1. CB750K4: Long distance bike, 17 countries and counting...2001 - Trans-USA-Mexico, 2003 - European Tour, 2004 - SOHC Easy Rider Trip , 2008 - Adirondack Tour 2-up , 2013 - Tail of the Dragon Tour , 2017: 836 kit install and bottom end rebuild. And rebirth: http://forums.sohc4.net/index.php/topic,173213.msg2029836.html#msg2029836
2. CB750/810cc K2  - road racer with JMR worked head 71 hp
3. Yamaha Tenere T700 2022

Where did you go on your bike today? - http://forums.sohc4.net/index.php?topic=45183.2350

Offline CycleRanger

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #11 on: October 18, 2015, 08:00:16 PM »
CycleRanger,

Only way we'd know is via information on the VIN Tag.  It gives the month and year of Manufacture.

It could be that the original owner changed out those parts after seeing a 77 or 78? ??? ???

I'm pretty sure they were not stock either on K6's.

Charlie

Yeah, it's an F front end. No, they weren't stock on K6's.
Do you have a copy of the Honda Shop Manual or Parts List for your bike? Get one here:
https://www.honda4fun.com/materiale/documentazione-tecnica
CB750K5        '79 XL250s     CL350K3
CB750K3        '76 XS650      '76 CJ360T

Offline 754

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #12 on: October 18, 2015, 09:06:22 PM »
It looks like an upside down fork on my tablet....
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline 70CB750

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #13 on: October 19, 2015, 05:26:45 AM »
I like the story too.

Following for the technical information.
Prokop
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Pure Gas - find ethanol free gas station near you

I love it when parts come together.

Dorothy - my CB750
CB750K3F - The Red
Sidecar


CB900C

2006 KLR650

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #14 on: October 19, 2015, 06:46:34 AM »
The removal of the gaitors and the relocation of the blinkers were done by previous owner to make room for fairing. I removed the fairing. While waiting for Marks availability to start the rebuild I have been doing some cosmetic restore. The front end is now back to stock with gators and proper fork uppers, and blinkers. I can post pics if I can figure out how to keep the thumbnails from inverting.

Offline Stev-o

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #15 on: October 19, 2015, 06:55:50 AM »

 I can post pics if I can figure out how to keep the thumbnails from inverting.

Are you posting from a tablet?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #16 on: October 19, 2015, 03:48:27 PM »
Yes, posting from an Apple Ipad

Offline dhall57

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #17 on: October 20, 2015, 04:16:47 AM »
You've already had quite a experience Woodtone with mother nature just getting the bike back home. I'm a owner of a K6 also so I'll be keeping a close eye on this thread for sure. Your bike looks nice. And with Mark doing the rebuild you know it will be done right. He didn't get the name Hondaman by accident ;)
1970 CB750KO
1971 CB500KO-project bike
1973 CB350G- project bike
1974 CB750K4-project bike
1974 CB750K4
1976 CB750K6
1977 GL1000
1997 Harley Wideglide

Offline Sgt.Pinback

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #18 on: October 20, 2015, 01:14:55 PM »
Restoration? ?

That bike looks great, especially the slightly faded colour.
Doc, I love a motorcycle!

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #19 on: October 21, 2015, 08:58:13 PM »
1976 CB750 prior to restore.

 
 

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #20 on: October 22, 2015, 06:03:05 AM »
Front end after. New wheels, new fork uppers, boots, polished hubs, forks and chrome fender. Blinkers are earlier version, smaller and clear lens.

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #21 on: October 22, 2015, 06:15:28 AM »
Pics of newly painted parts. I decided to go with a color that is similar to the original but with a bit more bling. Also went with earlier version emblems and tank graphics.

Paint products are from House of Kolor. Paint is amazing in person. Pics don't do it justice. Appears more burgundy in dim light and pops with gold shimmers in bright sunlight.
 

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #22 on: October 22, 2015, 06:19:30 AM »
Bike so far, this is how it looked before I delivered it to Mark for the mechanical rebuild.   

Offline Woodtone

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #23 on: October 22, 2015, 06:20:49 AM »
Oops

Offline Stev-o

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Re: Remarkable! An unusual 750K6 rebuild.
« Reply #24 on: October 22, 2015, 07:20:51 AM »
Very nice.  Who did the work to the front end?
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........