Build 76 KZ900 3-Wheeler?

I picked this project up in TN over the past summer at a residential auction. It was out of place amongst the dressers and clothes and was the last item to sell.
The owner told me after I won it that his son shipped it to him 10-15 years ago from Nevada where it was used on the sand dunes. Rear tires are Dick Cepek 25x13.5-9 Sand Sport.
The information I have found out so far is it's a 1976 KZ900 frame with a 1975 900 engine.
The exhaust and chain are missing. The rear sprocket is 60 tooth and 525 chain size. The front sprocket is 16 tooth and either 420 or 428 size, I forget which. A past owner must have been working on the chain and sprockets since the sizes are way different. In the photo, I had a 525 chain laying around so I'm seeing how many links I'll need. The rear frame and upper and lower trees look custom made for the 3-wheeler conversion as does the rear mono shock. I'm not sure if the front forks are original KZ or not.
It doesn't run of course so I will start with the carbs. It has individual K&N pods. The kickstart lever is missing so I can't kick it over.
The oil is full, but I'll change it and the filter first.
I've yet to figure out what the rear seat and fender piece is off of.
The gas tank looks to be from a KZ400 and is shot. The inside has been lined, but is flaking off with rust. Someone removed the petcock and filled the hole with epoxy and a 1/4" brass barb fitting where the hole was. When I pulled the fuel hose off, the fitting pulled right out of the epoxy. Also, they had used a plastic tee to connect the fuel lines to the carbs which is sticky and half eaten away from the old fuel. I showed all of this in photo.
Front tire was literally coming off in pieces when we loaded it at auction. Front rim is split style so new tire and tube have been ordered.
Someone's added rear disc brake setup off of a newer KZ? Maybe a 1000? I don't know the first year for rear disc on the KZ's?
Oh yeah, there's no front brake?!?!
That's about the extent of what I'm showing in the photos. Sorry, I forgot to take a photo with it all together before I started stripping it down.
I'll update more as I work on it more.

Thanks for saving that old Kawasaki from the burn pile. If it were mine, I would go for 530 chain and sprockets. You will have a wide variety of chains to choose from and you will not need a custom front sprocket, as there are 530 sprockets available for the kz. I do not remember which large KZ got a rear disc first, but that setup could be from most anything. (Yes guys, I promise I will get that chart to Bill soon.)

P. S. If you click the Insert All button before submitting a post with pictures, they will show up as large, high resolution pictures, and readers will not need to click on the thumbnails.

Looks like it was built by a decent fabricator. Not sure the rear axle looks stout enough. The outboard bearings look a little week for cornering.

It’s definitely a cool project.

I have seen a couple similar versions in the midwest area doing "TRIKE PULLS".I used to rodeo and been to every county fair and seen some crazy shit that I would never do and we rode bulls and broncs. Cool for sure, but made for soft ground and to go in a straight line for couple hundred ft.REAL FAST! looks like a quality builder did the work, as other have said.

Very cool project! Forks are definitely not Z1 or KZ900 or 1000. All of them bolt up on the bottom.

You have to be crazy to ride a bull!

Cool project!

First thing Id do is cap that upper shock mount with a piece of 1/4" plate.

Shankkole wrote: I have seen a couple similar versions in the midwest area doing "TRIKE PULLS".I used to rodeo and been to every county fair and seen some crazy shit that I would never do and we rode bulls and broncs. Cool for sure, but made for soft ground and to go in a straight line for couple hundred ft.REAL FAST! looks like a quality builder did the work, as other have said.

Hi Shank, seen your message, sending an email We used to Dirt Drag & sled pull also.
This was a 1075 with Andrews 3 X cams with smooth bores. Was fun of course, when everyone was drinking too! Had to sign off when you entered, At your own risk!

hardrockminer wrote: Very cool project! Forks are definitely not Z1 or KZ900 or 1000. All of them bolt up on the bottom.

You have to be crazy to ride a bull!

Depends on the BULL, this is my youngest a couple years ago. I know it looks crazy, but I was riding bulls at 7...... so normal has no standard to me. hahaha
THIS BULL IS A PET he was for pics like this with special needs kids etc.....

TexasKZ wrote: P. S. If you click the Insert All button before submitting a post with pictures, they will show up as large, high resolution pictures, and readers will not need to click on the thumbnails.

Thanks for the tip, I'll remember that for next time.

Kidkawie wrote: Cool project!

First thing Id do is cap that upper shock mount with a piece of 1/4" plate.

Thanks for that advice! I'll get that done.

Since I have to replace the KZ400 gas tank that was on it, I've been looking at original Z1 tanks.
The problem is all the Z1 tanks I see, on the underside where the tank slips on to the front circular mounts, the spacing is much wider than on the KZ400 tank.
If you look at the photos of the underside of the tank I took in my first post, you can see the distance between the front tank mounts. The tank fits perfectly on the front frame mounts on the bike.
I guess someone could have cut off the factory front tank mounts on the frame and welded on some 400 mounts. But why?
The 400 tank that was on it, someone also bashed in the back underside lip so that it would sit down on the frame. I don't want to do that if I find a nice 400 tank. Plus, the 400 tank just looks too small on the 900 frame.
Maybe a KZ650 or 750 tank has the narrower front mounts like the 400, but will fit the back strap and rear section of the frame so it won't need any hammer massaging. Anyone know?
There a cycle shop near me that has used parts. It's a shot in the dark, but I'll see if he has any tanks laying around.