76 KZ400 "Grimy"

Looks good Dan. I like the can dropped and shown better similar to Kiley's. No reason to have such a cool piece and not have it where it shows ;D

Thanks BLSully. I do too. I know they're not for everybody and they're not for build, but I like them on this bike.

Gary, thanks to you man, otherwise it would be a wallflower hiding back there behind the pods. And I agree, looks kind of race bikish sitting out there in the open.
I took BradJ up on his offer to build battery boxes and oil tanks:


I sent him some dimensions and we talked a few times and last week the mail lady delivered this:



It will fit right inside the top subframe rails right under the seat, basically the same way the plastic one did. However this one allows my K&N filters to fit. The back half is open on the bottom and back and will work as a sort of fender to keep water out from under the seat and will give me a spot to mount my regulator/rectifier that is hidden but open to the air.

I'm in the process of fitting and mounting it now. I have it ready to go in so I just shot it with a couple coats of satin black. I'm hoping to get it mounted in place tomorrow and then I can start figuring out how to make everything fit inside it.

The box looks and fits great, BradJ did a great job. If you need anything fabbed give him a shout.

Also I designed this with Google sketchup so give me a shout if you want a copy of the file for all the dimensions.
Kool im glad ya like it and it got there safe. you know where im at if ya need anything else
Hell yes! Finally some progress. Feels like I've been doing nothing but tearing shit apart the last few weeks. Things are starting to come together now. It took me several hours to get the electronics box to fit in place, because it fit like a glove. This evening I got the tray mounted, got the battery in place and then threw one of the carbs and filters on to check clearance. Purty. Now I just need to mount the rectifier/regulator and then put the rest of the electrics back together.

These 2 pics don't do it justice but none of the others I took tonight turned out any good besides this first one. It was just too dark in the garage, and though it was nice enough to have the garage door open this evening it didn't help provide any light.

I'm stoked the battery will stand up. That will leave plenty of room for the rest of the stuff.


I know this pic is bad but it gives an idea what the box looks like from the side. Damn sexy.


Feels like I'm heading in the right direction now.

Eventually I'll get someone to weld the box into place but the clamps are more than sufficient for now. Though I do need to paint them and the hardware black to subdue them a little.

Besides putting all the electrical bits back in place I'm about to order jets for the VM30s. I'm going to start with the settings that one of the guys from the Kawasaki Twins forum just reported that he's running successfully on his VM30s on his 75 KZ400.

His notes are:

The bike is a 1975 KZ400D. I'm running Emgo Pod filters and some aftermarket straight through mufflers on a dual exhaust system. Everything else is stock.

Best results for me were:
Main Jet: #230,
pilot jet: VM22/210 #25,
Throttle valve cutaway (slide): 3.0
jet needle: #6F5 on #4, (STOCK Needle, 1 Clip Richer)
Air Screw: 1.5 turns out
needle jet: #159 P-5, (STOCK)
air jet: BS30/97 2.0, (STOCK)
needle valve set: VM34/39 3.3, (STOCK)
float height: 22-24mm (STOCK)

As they come stock, the carbs were a little too rich on top and way too rich on the bottom end.

I did all the jetting with an air temperature of about 35F, so in the summer a couple of tweaks may be needed.

I started with 190 Mains and worked my way up until it would take full throttle without gasping for fuel. 230 worked well. The bottom was so rich with the #40 pilots it did not want to run cleanly at all. With the stock 2.5 slides in, I finally went all the way down to #22.5 pilots to get it to pull well on the bottom right off idle. There was still an off-idle "burble" when just cracking the throttle from a steady slow speed cruise, so I put in the leaner 3.0 slides. With this change, I went one step richer on the pilots to #25 so at idle, the mix seems good and just off idle that "burble" is gone. The new slide also leaned out the mid-range, so I raised the Jet Needle 1 notch to Position #4.

If you can live with that small "burble", you can set these carbs up to work about 90% well with just the #230 mains and the #22.5 or #25 Pilots. Even with just those two changes, it worked maybe 50X better than the CV carbs.

So it looks like I should probably order main jets from the stock 250 down to about 180 or so, pilots from the stock 40 down through 25 or 22.5, and a 3.0 slide.

Hopefully I'll have some better pics to share later this week.
I'm a couple steps closer after today. Thanks to George Washington for a day off and a beautiful day at that, got close to 60 degrees today with the sun shining. It would have been nice to go for a short ride but I'm more than happy with several mostly uninterrupted hours of wrenching in the garage.

I got everything wired back up and then did a little testing by turning on the ignition switch, checking all the lights and turning over the engine a couple of times with the starter button. All seems well so far.

I'm more or less happy with the wiring and organization of the battery and electronics. It's not perfect but I'll have to take this bike all the way back down eventually to have the frame painted or powdercoated so things are fine for now.

After finishing up the wiring I cleaned up the couple spots on the frame that needed it after cutting off brackets. Then I got the new 2-into-1 throttle cable in place. But after doing so I realized that it is not the right throttle cable - the ends are too big, they definitely won't fit into the mikunis. I've had this cable for a while and my bad memory lead me to believe I had bought it for the Mikunis, but I must have been mistaken. So now I have to add a new cable to the "To Buy" list. But luckily that was the worst news of the day and I'm happy with the results overall.

Jets for the VM30s are on the way. Hope to get those soon, order a new throttle cable and then get everything buttoned up and wait on spring.

Now some pics...



Please excuse that black/yellow wire bullet connected to the black wire that is running across the battery. I thought it was longer than it turned out to be. It will get extended and run around the battery. Darn, please excuse the masking tape on the fuse block too - just realized I had not removed it yet. I used it to label the wires that connected to it for reassembly.

Inside the box from front to back is starter solenoid, fuse block, and battery. Bolted under the rear shelf is the rectifier/regulator and I added a little shield over it made of lightweight aluminum to deflect most water/mud. On top of the shelf are the flasher and the relay used for the coil power mod. On my first attempt the flasher and the relay were inside the tray too and while they fit, it was a wiring mess. You can see that the stock seat latch is in place still, I'm still using the stock seat pan and everything fits underneath it well.



I sure did! Thanks Brad.

Not much to report since last update. Waiting on throttle cable and jets now. I also bought a "gently used" truck that has been taking up some time with minor repairs. But mostly I'm just waiting on the weather to get above freezing so I'll actually enjoy working in the garage and not just bear through it. It's supposed to finally get into the 50s next weekend and since I should have all my parts by then I think I can start wrapping this little project up.

The next little project is already calling my name... later model EX250/EX500 swingarms can be had complete, with adjusters and axle, for dirt cheap right now on Ebay - about $50 shipped.
Been a long time since an update but things started warming up and I finally found time to get everything buttoned up. Got the bike started up I've got it idling okay and can roll into about 1/8 throttle with little fuss. Next is to take it around the block a couple times to get it warmed up, feel for what's happening in the throttle transitions and tune as necessary. Now I just need my schedule and the weather to cooperate. When I've got other things to do: yard work, kids' after school activities, home projects or other vehicle maintenance the weather is great. When I have time on my hands it always seems to be raining.

But I finally got her down from the bench Saturday, rinsed off all the dust and I snapped some pics this evening in between rain showers.

I got photobombed by my daughter in one pic and by our old toilet that is sitting in the garage in another.













I did a few other small things over the weekend too. I stripped the black paint off the controls, took them down to bare aluminum. I painted the rear fender satin black. And I took the front fender off to paint it satin black too but decided to leave it off for a while. Now that everything looks so nice and minimal I'm really hating the stock tach and speedo. They just look too big and I'm going to have to change them out for something smaller. I think the headlight ears need to be black now instead of chrome too and maybe the same with the headlight bezel. I also didn't notice how long the speedo drive cable was until I saw these pics. Those tires are fine for the street but the bike would look very cool with some tires with a little more dual-sport look, but I'm going to ride with these until they wear out. I really wish the handlebars were black instead of chrome. The brake light housing needs to be black instead of chrome or I need to swap to a single light with integrated turn signals, black of course. Now that I see the battery/electronics tray in place I think that I could have gotten by with it 1/2 or 2/3 as deep as it is now and I think it would look a lot better. I could go on an on.

All that said, it's looking pretty good IMHO. And it's hard to tell without a rider in the pic for context but it is low and lean and mean. I'm planning on sneaking the bathroom scale down to the garage and weighing it tomorrow while the wife is at work :)
Bike is looking good sir!

Your initial tuning notes sound a lot like mine.... try those 2.0 slides, I'll bet it makes a world of difference. Raising the needles seems to help to some degree, but if it's just falling on it's face over 1/8 throttle, it didn't seem like the needle alone could compensate on the VM32's. I have a set of 6F4 needles I want to try as I still have a pretty interesting flat spot I'm not entirely sure how to be rid of.

Good luck, will be watching.
I like what you've done with your kz. I just picked up one myself, hopefully it will turn out as nice as yours.
Great work, it's looking awesome!

I have a '79 KZ400 that I've been messing around with lately. I've just been taking my time on things like new bars, cleaning the rusty tank, new petcock, hoses, making a new seat, general cleaning etc. Seeing how nicely your build is coming along makes me want to pick up the pace a bit.
Thanks guys.

Not much going on this summer due to a move. Great move for me since the new house has a huge pole barn with plenty of room for wrenching on bikes and plenty of room for more bikes.

Only thing I changed recently was swapping out my rear signals and taillight for an integrated unit.

It would be nice if it wasn't plastic but it does have the right look and functionality so I can live with it.
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