My (I refuse to give it a name) '78 KZ400 B cafe conversion.

biker_reject

Over 1,000 Posts
OK, here goes. This was given, yep, that's right - given to me last Sept. by a buddy for helping him move back to town. He bought it in VT and used it to learn how to ride street. I felt so guilty for accepting this offer that I gave him a barely used flyrod! I dig the kick start.
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So, I began tear down over the winter. Engine was crusty, but ran two years prior. 21k on the clock, lots of leakage from the bottom end. Exhaust was toast with rust holes in both cans though the head pipes look good.
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I set that aside and chopped on the frame a little. This spring, I started stripping the tank.
I encountered the first headaches - dealing with wheels. The front hoop was just about perfect, the rear was really bad with rust eating pinholes from the inside of the rim to outside. Looked for replacements on flee bay and they all looked terrible. I bought one that the seller claimed was not too badly corroded and would clean up with a wire brush. That turned out to be total bull shit. This was the best I could do with a wire wheel.
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I had it blasted and the pits were so deep that no amount of powder would cover it. Frack Powder coat guy suggested a type of coating that H-D guys were using that was heavy and textured. I gave the go ahead and was pretty pleased. It resembles sprayed on truck bed liner. Very heavy, very tough. I bought a front hoop off ebay and had it coated with the same stuff. Good hoop to be sold off for big bucks, I hope. Next issue was finding rear spokes. Front spokes in remarkable shape. Took months to find OEM rear spokes and I never got them all. I had to take 8 of the best original spokes and use them. Not the best look, but I was not about to pay what Buchanan's wanted. The thing that made me think of a dual brake set up is that the KZ400 front hub, once the chrome caps are removed (4 Philips head screws) is treaded on both sides for rotors! Awesome discovery.
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Jumped the gun before finding a good rear wheel and cleaned up and mounted a tire on the beautiful front wheel. Frack Had to pull the tire off, spokes off, and wait for what seemed like an eternity to find a decent hoop to powder.
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In the mean time, I was making progress on my XV750 project with an R1 front end swapped in. That gave me the bright idea to do some kind of swap on the KZ. I was intrigued with the anti-dive systems of the 80's that Yamaha and Kawasaki did, all those fins and brake lines and shit sticking out. I chose a GpZ front end, but all the ones I saw were in really bad condition. I finally came across a complete front end from a '85 ZX600 GpZ. That brings me to headache #2 - the corroded anti dive valve. I pulled the first one to clean and look over. It looked great, The second valve...
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The only valves I'd seen for sale were selling for almost what I paid for a complete front end! I decided to leave it as is in the middle position where it remains rusted permanently. Problem solved! The project right now is focused on the front end. Oh yeah, I swapped the stems to complete the triple tree swap and replaced the ball bearings with upgraded tapered units from AllBalls. Later, I had a machine shop turn down the GpZ front axle to fit the KZ wheel. Worked out pretty good, but I have to shim the calipers just a tiny-tiny bit to center them over the rotors. Watching for a decently priced rotor on flea bay. Some of those sellers are nuts with what they're asking!
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Plans are to next chop more of the rear frame in order to change the rake of the bike without major changes to suspension. Then a pair of RYF reservoir shocks. Trying to find sprockets for a 520 chain conversion. It's beyond me why a 36hp bike needs a heavy ass 530 chain. What up wit dat??? I ran 520 chains on my sportbiikes! :-D Finally, attention turns to the engine and exhaust. I give this project a year at the most. I think I'm being optimistic! Ha!
 
Gonna rake the seat a bit and perhaps reposition the angled down tube to clean up the rear since there won't be a battery or anything under the seat area. All the electronics will go under the seat cowl. I didn't want to get longer shocks (though that is still on the board) or drop the forks through the trees a whole lot. In other words, I want to keep the suspension geometry stock or as close to it as possible. Another member mentioned in another thread that I could change the angle of the tank and seat without mucking about the suspension geometry.
 
My inspiration came from this dude on kz400.com
 

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The overall look is inspired by the blue and silver bike. I want to give mine a more aggressive stance without changing the suspension geometry. What I'm thinking of doing is lifting the rear of the gas tank up a couple of inches at the most and tilting the subframe up in the rear. In the last pic of my OP, I've jacked up the rear of the tank about 2" with a block of wood. Kind of hard to tell though without the seat cowl at the same level or angle. The angled down tube I'm thinking about reducing the angle or replacing it with curved tube, just to "air out" the rear end. I come from riding sport bikes, you see, and what does it for me is the raked stance and clean rear end of a modern race rep. I strive for that look in a cafe style bike. I think it makes a machine stand out from the rest without being too radical. I experimented with the stance on my cb750 DOHC and I finally got it the way I want. With this bike, I hope to achieve it without a lot of experimentation!
 
I wish I had Paint on my desk top. But I don't have a program like it on this new puter. I could show you easily if I did. But, instead of a tube that came off the main frame straight to the shock mount area, the new tube would come off the frame at a higher point, or (from original mounting point), curve upward and be welded to the shock mounting point. I'm thinking the curve would follow the same radius as the rear tire? This way, I think I can achieve a more open/unobstructed area behind the engine.
 
Well, no, I don't want to weaken anything! I could go the route of my cb project and weld an "H" frame to the top of the existing subframe as a way to raise the seat height.
 
Drilled out left rotor Friday night... Can't wait for the other rotor to arrive!
 

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Not much of an update, but I finally found a front rotor in good shape and thickness, only this one was covered in what the seller called an "iron oxide paint". I have no idea what the hell that is, but it was applied really thick - like it was poured on! I'll see if stripper has any effect on it. If not, off to a blast cabinet. Gonna drill it out tonight!
 

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Had the "new" rotor blasted (gotta get my own blast cabinet), painted both rotors centers black, drilled out second rotor. Almost done with the front end. I'm thinkin' it looks pretty trick! After stepping back, I think the front end is just screaming for a fork brace.
 

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While scouring FleaBay for kz stuff, I came across and scored these ZZR550 shocks for $69 free shipping! WOOT Also scored a 2 into 1 exhaust in really good condition. Not as exciting as the shocks, but a significant find. So, 2 major components to my project suddenly appeared at the same time. Hooray fo me!
 

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I have brand new needle bearings for the '78 swingarm if you're interested? Just pay shipping. I bought them accidently (76 takes bushings! derp)
 
Nice find, I got a set of those last fall. I just took one of them apart yesterday. I am deciding if I want to make a new seal head or just clean everything and reassemble.

Did you get a stock exhaust or aftermarket?
 
Would you happen to have some pics of the dismantling process? I was looking for a split ring type spring seat, but they don't have them. So before I compress the spring, I'd like to know what steps are needed to take them apart. The exhaust looks aftermarket, but I don't know the brand. This was an important find because the original exhaust had a dented header pipe and corroded cans. I had planned on just buying a new Mac, the only choice out there, but used and $75 ($49.99 + $25 S&H) beats $200+.
 
No I didn't take any pics, maybe on the second one.

I have a spring compressor that I built, it holds the shock upside down and uses a threaded rod to push the retaining ring down and hold it in place. Then there is a wire type circlip that you need to remove and then you can take the spring off.

There is one small allen bolt you will see on the lower part of the shock that needs to be removed before you do anything else.

You may be able to get the spring off with two people, (one pull the spring down and the other work on the circlip)

Another hillbilly way would be mount the shocks on the bike, use a ratchet strap from the swingarm to the frame and compress the shocks, then use a bunch of zipties around the spring coils, release the ratchet strap and remove the shocks. Then you should be able to get the ring off.
 
Hey thanks! I have a spring compressor. I didn't know about the circlip though. That's helpful to know. On the bottom of the shock's reservoirs, there is a cap that covers a Schrader valve. One of my shocks is missing this cap, and the other one still has one on. It looks like the PO tried to get it off but couldn't. I assume you removed yours for rebuild? If so, how did you get them off?
 
Okay, yeah you need to take that little bolt out then, then there is an outer ring that will move down with the spring, then there is a sleeve that you will slide down to get to the clip.

For that cap I heated the outer res. just a little with a propane torch and then used a really small flat screwdriver and carefully, little by little pried it out. Didn't mark anything up to much.
 
OK, I understand. I was thinking the same thing with the cap, but didn't know if heat would damage anything. The PO looked like he tried to bang it out with a small screw driver. I'll give it a shot. Thanks again, Bro!
 
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