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1976 KZ400-S2 Cafe/Brat

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17 Oct 2015 17:43 #694982 by ZeffRides
Replied by ZeffRides on topic Re:1976 KZ400-S2 Cafe/Brat
Alright so its been a couple weeks since my last update, been a little busy with class/work. However I've got some exciting news and I think you guys/gals will appreciate the results. Today I silica blasted all the rattle-can paint off and was left with these amazing results!

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Tomorrow I will hopefully get the raised rear frame cross section chopped and the loop welded in. Then degrease the frame and get it primed!

1976 KZ750B1
1978 CB750K
2002 BMW 530i 5-speed
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18 Oct 2015 07:36 #695053 by loudhvx
Replied by loudhvx on topic Re:1976 KZ400-S2 Cafe/Brat
Nice progress. Now if I could only erase my memory of the rattle can job the same way. :laugh:

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18 Oct 2015 07:43 #695054 by loudhvx
Replied by loudhvx on topic Re:1976 KZ400-S2 Cafe/Brat
The 1976 carbs are not super hard to get tuned without an airbox, but an airbox is always a good starting point to make sure you don't have other issues. ... most common would be vacuum leaks in the carb holders, and mismatched fuel level, petcock flow, tank vent, and then, of course all other motor related issues... compression, valve lash, points timing.

There are so many variables, it would be nice to eliminate a bunch of them by starting with the airbox. If you don't have one, it;s not the end of the world, though. It will just take more time (like several days) to dial it in.

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18 Oct 2015 20:51 #695138 by ZeffRides
Replied by ZeffRides on topic Re:1976 KZ400-S2 Cafe/Brat
I plan on keeping the stock airbox for the time being to assist in carb tuning.

On another note I made some more progress today! Got the frame cut and rear loop fitted and welded.


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Next I will degrease the frame and get some self-etch primer on it to prevent flash rust. A good friend of mine owns a successful collision repair shop and said the aluminum engine block should be okay without paint as long as all bare metal pieces it contacts are coated. What are your opinions on this?

1976 KZ750B1
1978 CB750K
2002 BMW 530i 5-speed
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29 Oct 2015 10:51 #696425 by lopro
Replied by lopro on topic 1976 KZ400-S2 Cafe/Brat
Nice progress thus far.

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08 Nov 2015 10:02 #697752 by ZeffRides
Replied by ZeffRides on topic Re:1976 KZ400-S2 Cafe/Brat
I've been slacking on keeping my thread updated the past couple weeks but I've still been working on the bike when I get the chance! I initially painted the frame with some rustoleum enamel and then got worried about how well that was going to hold up so I decided to start over and repainted with VHT Rollbar and Chassis paint. I'm pretty happy with how it turned out, its not perfect but its better than it was!

A couple weeks ago I also dissembled the forks and cleaned them out really well, then got them rebuilt and new seals from All Balls installed. Taking them apart was kind of a pain due to the inner circlip holding everything together. I figure that by using a large bar clamp with the end that screws out, I could get the top plug pushed down and hold it there with the clamp, which gave me room to remove the circlip.

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Today I attached the swingarm and fitted my engine mounts on so I could remember what goes where. Later this week I should have some extra time to get the engine back in and work on the steering stem. I ordered tapered bearings to replace the loose bearings that used to be on the stem, should be much better than it was!

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1976 KZ750B1
1978 CB750K
2002 BMW 530i 5-speed
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08 Nov 2015 10:22 #697755 by davido
Replied by davido on topic Re:1976 KZ400-S2 Cafe/Brat
Next I will degrease the frame and get some self-etch primer on it to prevent flash rust. A good friend of mine owns a successful collision repair shop and said the aluminum engine block should be okay without paint as long as all bare metal pieces it contacts are coated. What are your opinions on this?

The guy that rebored my engine also 'ice' blasted the head and barrels. He told me there was no need to do anything with it ,that the finish was good to go.( I painted it anyway as Id always planned on a black engine.)
At my local bike shop,I grit blasted a couple of aluminium parts and was told to just wipe over them with diesel and theyd be good to go.
Take from this what you will .
Enjoying you build.Good luck with it.

www.kzrider.com/forum/11-projects/594313-csr1000-project-build
CB550 (1978)
CB500/4 (1972)*
KZ1000CSR (1981)
XT 600E (1999)
TDM900 (2003)

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08 Nov 2015 12:02 #697776 by ZeffRides
Replied by ZeffRides on topic Re:1976 KZ400-S2 Cafe/Brat
davido, thanks for the advice! That makes me feel better about leaving the engine bare. The blasted texture is really cool so I'd like to keep that. I may eventually paint part of the engine but not for now.

1976 KZ750B1
1978 CB750K
2002 BMW 530i 5-speed

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16 Nov 2015 08:45 - 16 Nov 2015 08:47 #698956 by ZeffRides
Replied by ZeffRides on topic Re:1976 KZ400-S2 Cafe/Brat
This weekend I managed to find some extra time for the bike. Got the engine mounted and in the process I chipped the paint of the frame unfortunately so I'll have to do some repair there. :pinch:

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Then got the wheels back on...

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And finally added in the remaining frame fittings

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After all that was on I reinstalled my clutch cable after cleaning out the clutch release mechanism and adjusting the clutch, then i Installed the front and rear brakes and adjusted both of those according to the manual. I also did a little cardboard aided design trying to get an idea of where I can fit a small electronics tray for my fuses and R/R. However, with the stock airbox still installed I'm extremely limited so that battery will have to stay in the stock hanging location :(

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Next I need to check float heights in the carbs, get those sealed up and installed. After that probably going to adjust my valve clearances, cam chain tensioner, then sync carbs and HOPEFULLY i'll be running smoothly by that point. Once I get everything running well I repair/replace things as i see fit as the budget allows.OH and I will eventually figure out something to do with that awful mess of a seat that is on it currently. Most likely going to fiberglass a new pan and attempt to keep the stock hinge and frame mounts.

1976 KZ750B1
1978 CB750K
2002 BMW 530i 5-speed
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Last edit: 16 Nov 2015 08:47 by ZeffRides.

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05 Dec 2015 13:51 #702044 by ZeffRides
Replied by ZeffRides on topic 1976 KZ400-S2 Cafe/Brat
Finally got around to figuring out what to do for the "seat pan." Decided to use wood because that's what I'm comfortable with and what I had the tools for. Heres what I did.

Materials:
1" wide strip of sturdy metal ($5)
1"x12"x8' common wood ($5)
Four .25" x 1.5" chassis bolts ($2)
Four .25" wingnuts ($1)
1/8" rivets ($3)

First I cut/ground off all the stock seat mounting hardware and seat lock so the pan could sit flat. Cut the 1" strip to fit across the subframe and pop-riveted it onto each side. Used a piece of cardboard to make a template for the pan, transferred that onto my 1"x12" board and cut to size, chunk cut out by the tank is for the negative ground/battery mount. Marked and drilled 2 holes per strip. Mounted the chassis bolts through the pan and into the strips and tightened down with wing-nuts. Super simple, functional and less than $20! I'll figure out whether or not I want to do some padding myself or have it upholstered by someone else.

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1976 KZ750B1
1978 CB750K
2002 BMW 530i 5-speed
Attachments:

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