Topic: 1978 cb750k- and so it begins

[Dime]

Here is the unsightly top clamp, LOL

[calj737]

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.

[Dime]

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.

[Dime]

Pulled the head and the cylinders. Pistons are stock and have a lot of scuffing on the skirts. Definitely looking at a rebore.

[Dime]

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.

[Dime]

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.

[Dime]

The sprocket looks pretty close to being in line

[Alan F.]

Nice! I've messed around with stuff like this before and its always fun to follow along.

[Dime]

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. 

[Alan F.]

It makes me wonder if the engineers at Kawasaki dissected a cb750 and based some things on what they found?

[Dime]

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.

[Dime]

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.

[Alan F.]

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.

[Dime]

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.

[Dime]

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.