The Creature from the Black Leather Lagoon ('78 KZ1000)


Been Around the Block
Here goes.

Last year, I bought this non-running '78 KZ1000 LTD:


Aside from the PO having removed and disposed of the rear fender and tailpiece, and having cut off the exhaust pipes right behind the collectors (apparently with a sawzall), pretty nice bike. Like a lot of loks my age (50 in a couple months), I've been a fan of the big Zeds since I was a kid and saw Mad Max on a buddy's parents' Betamax player.
It had good enough compression (mid-120's) on all 4, and a happy surprise:


So I picked it up and went through the electrics, where I found a handful of cold solders and bum grounds. In about a day, I had it running okay, so I picked up a Delkevic 4:1 exhaust

Silencer on Bike.jpeg

Cleaned and rejetted the carbs

Float Bowl.jpeg

Poppped a set of Uni filters, some Dynatek coils, and fresh plugs and wires on, and had a nice running old machine...for a minute. It started running like crap, and the compression uniformly dropped by half, so I bit the bullet and tore into the engine to find this


A cam chain guide that broke in half and distributed bits of itself all throughout the engine. I've sent the case halves, cylinder block, and head (in which, I'm glad to say, the valves are unbent and good to go) to be vapor honed. Also, I've ordered new cam chain guides, idler pulleys, cam chain tensioner, and rubber dampers—pretty much the whole timing system was garbage. In the meanwhile, I'm doing a little arts-and-crafts


and drilling


As long as I've got it stripped down to the frame, I'm also going to get a frame bracing kit from Half Evil Customs. Apparently, these mahines are somewhat prone to frame flexing on an aggressive lean. I thought about trying to fab a kit on my own (I read somewhere that Pops Yoshimura donated the world a set of plans for bracing these bikes) but decided that, given my lack of fabrication equipment (and skills) and the price of metal at present, $170 after tax and shipping was a pretty good deal for a complete kit that takes out all the guesswork.
So now that it's in bits and pieces, I've decided to reimagine this bike. I looked through my stuff and found a headlight bucket from an RD 400 that whispers "cafe racer" to me. I also found a set of Valter Moto rear sets I've had hanging around for a long time, and I made some mounting plates for them from 3/16" mild steel


And I mocked up a new seat. I'll put images up for that soon, and I'll definitely be soliciting advice about it. Thanks in advance!
This was my first stab at a new seat:


Incredibly uncomfortable and kinda dumb looking. So I went back to the drawing board and remade it with the bump stop at the same angle as the forks (26 degrees) and that looked and felt a bunck better. I couldn't leave well enough alone, so I used that seat as a mold for a fiberglass duplicate. I made that in 3 pieces—salt pan/electrical tray, seat cowl, and upholstery plate. I'm envisioning the cowl attaching to the seatpan with Dzus fittings. I won't be near the shop until after the weekend, so I'll post pics then.


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Off to a great start. Can't wait to see where you go with this.
Thanks so much. This was the second seat I made from sheet metal:


Way better in terms of looks and comfort, but it weighed a lot more than the stock seat, and didn't offer much space under the cowl for electrical stuff, so I used it as a mold for a fiberglass cowl, and made this fiberglass seat pan:


The four holes in the front are for the (not yet) upholstered piece, and the four holes in the back are for the cowl to attach with Dzus fittings. Here it is with the cowl:


And here's the whole shebang


Clearly, I've still got a good bit of work to do with a DA sander, to say nothing of my impending first stab at upholstery work. Still, I'd love any input about the design. Particularly, what am I not thinking of that might consttute a fatal flaw of this system?

Assuming nobody points out any deal breakers, I'll weld a couple pieces of flat stock across the frame rails and drill them out where the 4 bolts travel from the (un)upholstered piece go through the seat pan. I'll probably do that when the frame brace kit shows up, so I can do all the grinding, welding, and appliance epoxy-ing in one go.
Cool build. looks like you have a pretty bitchin shop there too. I also have a '78 LTD that i did a resto-mod thing to.

The problem I found is when converting to a low profile seat on these bikes is you loose quite a bit of seat height since the originally was so thick and a good 3/4" above the frame rails. the frame rails are relatively low.

This is particularly a problem if you are raising the foot-pegs with rear sets. I ended up cutting off the rear sub-frame and raising the top rails about 1.5" to accommodate a lower profile seat and maintain the stock seat height. You can correct the top shock location point at the same time and get a better shock angle while you're at it. YMMV.
I'll look more closely through your build (which I've been admiring, both here and on kzriders). Do you know if a sub-frame redesign like yours will play nice with the Half Evil frame bracing kit?
im not familiar with that kit but if its the usual stuff the only one that would change is the gusset by the upper shock mount. But if you are capable to do a sub frame redesign remaking a gusset will be inconsequential. there are other ways to get the seat hieght up but depending on your stature it may or may not be worth it. Im pretty tall so not being cramped was important for me. look at the rear of the tank and you will see how high the stock seat comes up.
I climbed up there when I first put the rearsets and clip-ons on the bike, and it felt good to me (I'm about 5'10"), but I wonder if the handling might benefit from raising the center of gravity a little. I'll do some head-scratching and soul searching now, while making changes to the frame is relatively simple.
Since I'm going to clip-ons I cut the clamps off the top triple, and learned a tough lesson about metallurgy. I got almost all the way through with a cutoff wheel on an angle grinder, then grabbed it to twist the remaining little connection, like one might with mild steel. Come to find out, cast aluminum doesn't like that, and I busted out a big chunk so, instead of having four nice round holes, I had three nice round holes and one ovoid-type thing. So what should have been a straight forward cleanup with a flap disc turned into a bunch of work with a die grinder, Dremmel tool, DA sander, and angle grinder before I came up with something pretty much symmetrical:


Lesson learned, and onward I go.
I decided, while I've got it apart, I might as well tart up the cylinder block with some high temp paint:


I'm happy with how it came out. It was a good deal of sanding, razor blade work, and tiny paintbrush touchup, but I think it was worth it.
At the school I work at, a colleague was going through the inventory left over from a former robotics instructor, and brought me about 10 of these boxes, dismayed that we were saddled with so many of the very same size machine screws:


I promptly told him that I could find a good use for a whole bunch of them:



Sorry about the artsy B&W picture; I'm still getting used to my phone...
At the school I work at, a colleague was going through the inventory left over from a former robotics instructor, and brought me about 10 of these boxes, dismayed that we were saddled with so many of the very same size machine screws:
That’s like $500 worth of stainless at my local hardware store! Jackpot!
I promptly told him that I could find a good use for a whole bunch of them:
Second job on my SR250 was to get rid of mangled JIS screws from engine covers and replace them with ss Allen bolts.
Most convenient mod ever :)

Fiberglass butt looks sleek :D
They were tossing a pallet of parts at work a couple decades ago. I still have a bunch of button-head metric Allen head ~4 - 8mm. Use some on most rescues. Not helpful on the '72 Triumph T150V that I'm working on right now, though.
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