Author Topic: 1978 cb750k- and so it begins  (Read 5328 times)

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Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #25 on: October 27, 2024, 03:37:29 PM »
Here is the unsightly top clamp, LOL

Offline calj737

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Re: 1978 cb750k- and so it begins
« Reply #26 on: October 27, 2024, 07:46:06 PM »
Now that being said I will not be using the top clamp. I will be sending it off to a fabricator I follow in Nova Scotia so he can machine a new top clamp out of aluminum.
Then simply have him machine the 1.6mm relief in the stem area so the stem protrudes enough for the nut to capture it.
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Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #27 on: October 28, 2024, 04:47:22 AM »
Now that being said I will not be using the top clamp. I will be sending it off to a fabricator I follow in Nova Scotia so he can machine a new top clamp out of aluminum.
Then simply have him machine the 1.6mm relief in the stem area so the stem protrudes enough for the nut to capture it.

The issue is that the bearing area starts shorter on the kawi tree. Just dropped it off to have them press it out 1.6mm to match the cb750 stem.

The reason for machining the new top clamp is because all the extra parts on the stock kz1000 ltd clamp are unnecessary. So this will clean it up nicely and give a modern look.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #28 on: November 02, 2024, 06:14:57 AM »
Pulled the head and the cylinders. Pistons are stock and have a lot of scuffing on the skirts. Definitely looking at a rebore.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #29 on: November 05, 2024, 09:07:32 AM »
So the machine shop couldn't press out the stem on thr kz1000 ltd triple tree. So I had to dust off some of my machine shop training and get to work with an old school bastard file to machine the aluminum at the bottom of the stem where the bearing sits.

My old shop teacher taught me a trick to reduce a raised edge around a stationary round object. You file a  notch into the edge to the depth you need. In a counter clockwise direction you move around the circular object overlapping your filed section. This brings the next filed section down to the last. Just keep doing that until the entire edge is down to desired level.

Of course you check your depth every few mm's to confirm the height is remaining the same throughout the entire piece.

In total I removed 1.6mm and now I have the proper stem length to work with the cb750 frame.

This took a considerable amount of time and a gentle touch. In the end it cost me $10 for a new file small enough for the job.

Now to get the conversation bearings ordered.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #30 on: November 07, 2024, 03:04:20 PM »
Can't say for 100% certain that I won't have to shim the rear sprocket but it looks pretty good.

78 cb750f swingarm and axle. 1981 Kz1000 ltd wheel, disc, axle spacer, floating caliper mount and caliper.

Everything lines up like it should. Will need to have some custom spacers done, but can't finalize any of that till engine is back in the frame and I do alignment.

I am going to go ahead and say this will work. This is going to look great IMO.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #31 on: November 07, 2024, 03:05:27 PM »
The sprocket looks pretty close to being in line

Offline Alan F.

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Re: 1978 cb750k- and so it begins
« Reply #32 on: November 07, 2024, 04:10:23 PM »
Nice! I've messed around with stuff like this before and its always fun to follow along.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #33 on: November 08, 2024, 02:54:50 AM »
Nice! I've messed around with stuff like this before and its always fun to follow along.

It is a bunch of fun for sure. I am surprised just how easily the kz1000 ltd parts are going on the cb750. 

Offline Alan F.

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Re: 1978 cb750k- and so it begins
« Reply #34 on: November 08, 2024, 10:26:20 AM »
It makes me wonder if the engineers at Kawasaki dissected a cb750 and based some things on what they found?

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #35 on: November 08, 2024, 10:47:34 AM »
It makes me wonder if the engineers at Kawasaki dissected a cb750 and based some things on what they found?

I wouldn't doubt it. The fact the kz1000 ltd and the cb750 share a 20mm rear axle makes one wonder.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #36 on: November 08, 2024, 04:06:32 PM »
Other than a potential issue with the frame, there is some thought it might have been repaired, I have centering cones on route to check the neck alignment. I don't think there is an issue but it is better to be sure.

I think the 19" front and the 16" rear is going to give this just the stance I am looking for.

Offline Alan F.

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Re: 1978 cb750k- and so it begins
« Reply #37 on: November 10, 2024, 12:40:50 PM »
I just took a look thru my K8 thread for good photos of the left side of the neck welds before I painted the frame, hope this helps.


Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #38 on: November 10, 2024, 12:49:39 PM »
I just took a look thru my K8 thread for good photos of the left side of the neck welds before I painted the frame, hope this helps.

That definitely helps man. Thank you. It confirms that I am missing that bracket for sure. While I can't see the welds in your picture that I have potential issues with I can tell that these frames were not welded up to my standards. They are fine and I am not a professional welder, I do have courses on welding and fabrication, but I am not a fan of what I am seeing. Penetration wise I have no doubt it is good. It would not of held together this long if that was not the case. How it was laid down is lacking. A pretty weld is not necessarily a good weld but it is nice to see a properly laid down weld with good penatration.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #39 on: November 18, 2024, 10:15:11 AM »
In the process of mock up for the rear master cylinder, reservoir, and spindle. Nothing is set in stone as I am waiting for my buddy to get the progressive shocks off my old bike so I can put them on this one. Then I will have a better idea of how it is all fitting up as well as hose routing.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #40 on: December 12, 2024, 08:52:27 AM »
My buddy hooked me up with these progressive shocks today. They came off my old cb750 dohc. They need new bushings and a good cleaning up but otherwise in great shape. I found them really good on the dohc. Free is always a good price.

I have to get some line for the brake reservoir to the master cylinder. The reservoir is just mocked up now, not sure it will clear the seat in current position.

Overall I am happy with it thus far.

Offline Kelly E

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Re: 1978 cb750k- and so it begins
« Reply #41 on: December 12, 2024, 11:46:31 AM »
Other than a potential issue with the frame, there is some thought it might have been repaired, I have centering cones on route to check the neck alignment. I don't think there is an issue but it is better to be sure.

I think the 19" front and the 16" rear is going to give this just the stance I am looking for.

It should end up with a stance like this, 19" front and 16" rear with Progressive shocks.
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The Rust Bros. Garage Collection
1974 Honda CB 550 K0                                            1971 MGB/GT
1975 Honda CB 400F Super Sport                          1972 MGB/GT
1977 Kawasaki KZ 1000 LTD                                   1985 GMC S15
1978 Kawasaki KL 250
1980 Suzuki GS 1100E
1982 Honda CB 900F Super Sport
1983 Honda CB 1100F
1984 Honda VF 700S Sabre
1984 Honda VF 1000F Interceptor
1990 Moto Guzzi 1000 Le Mans
1994 Kawasaki Concours ZG 1000A9
2005 Harley Davidson Fat Boy

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #42 on: December 12, 2024, 11:56:24 AM »
Other than a potential issue with the frame, there is some thought it might have been repaired, I have centering cones on route to check the neck alignment. I don't think there is an issue but it is better to be sure.

I think the 19" front and the 16" rear is going to give this just the stance I am looking for.

It should end up with a stance like this, 19" front and 16" rear with Progressive shocks.

That is basically what I am looking for except the boat tail. Mine will have a shortened rear fender and lucas taillight. I also think the cb750 sohc engine looks better. Oh and I will have z bars.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #43 on: December 14, 2024, 07:40:20 AM »
Found this picture online. Mine will look different but it is pretty close to the stance I think mine will end up like. This 750 has 18" front I think but pretty close

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #44 on: December 15, 2024, 08:49:05 AM »
Found a picture of a cb750 sohc with 19" front 16" rear.

Love the stance

Offline Alan F.

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Re: 1978 cb750k- and so it begins
« Reply #45 on: December 15, 2024, 03:43:19 PM »
I like that look. My Royal Enfield Interceptor 650 came with 18's front and rear. I went to a 21" front and its great. I'm thinking about a 17" rear but i doubt the ABS will allow it.

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #46 on: December 15, 2024, 03:46:25 PM »
I like that look. My Royal Enfield Interceptor 650 came with 18's front and rear. I went to a 21" front and its great. I'm thinking about a 17" rear but i doubt the ABS will allow it.

Nice scoot man. It looks great.

Offline Alan F.

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Re: 1978 cb750k- and so it begins
« Reply #47 on: December 15, 2024, 03:50:28 PM »
Thanks Man, its not much of a mile eater but im working on it.  Its similar to an old bike but has some modern stuff. It reminds me of a Bob Seger song, "He wants to dream like a young man
With the wisdom of an old man
He wants his home and security
He wants to live like a sailor at sea..."

Offline Dime

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Re: 1978 cb750k- and so it begins
« Reply #48 on: December 15, 2024, 05:07:49 PM »
Thanks Man, its not much of a mile eater but im working on it.  Its similar to an old bike but has some modern stuff. It reminds me of a Bob Seger song, "He wants to dream like a young man
With the wisdom of an old man
He wants his home and security
He wants to live like a sailor at sea..."

I like those throwback bikes. You get the best of the modern with a nod to the older style. They have their place like any bike. I am not a purist by any stretch so those type of bikes are right up my ally. My buddy that I bought my cb750 off of has a 69 Bonneville as well as a newer triumph. His newer triumph sees more action than the classic.

That is what I like about the cb750, the following is almost as big as Harley but the cost is far less for parts. Once I have mine on the road the upkeep will be minimal. My Harley cost me a fortune between maintenance and customization.

The cb750 may be a classic but it is relatively inexpensive.