LZ's 76 KZ900

So I think it is about time I start working on my KZ900. I have always wanted one, and fortunately I saved one from a friend who was going to scrap it for extra money to pay some fines. I bought it off him for $50 without a title. After quite a bit of running around and some extremely helpful people at my MVD, I had a title the next day.

Well this thing was and is a total mess at this point. What else can you expect for $50?

This thing has been sitting outside for so long that nobody in his family seemed to remember what the original color was before his grandfather got a little crazy gold paint.

So far, the engine would spin freely by kick lever.

Most of the wiring seems to have been messed with.

Front brake lever is locked up.

I could write a whole list, but essentially the whole thing needs to be gone through. Especially when the compression ratings I was getting were around 120-80-80-90. Wet test improved it quite a bit. I was hoping at first it was just stuck rings, but I had let everything soak for months in penetrating oil before doing a compression test. Oh well, good excuse to rebuild the motor.

So that is where I am at. I have never rebuilt any motor before. I have worked quite a bit on various bikes and cars but never had the fun of slipping a new piston through a fresh cylinder.

So I need all the advice you generous people may have to help me in getting started on rebuilding the motor.

I am thinking at this point I will start from the bottom up

I want to get the crank welded and balanced. (Falicon?)

I was considering getting the transmission teeth undercut (if I am saying that correctly). I was told it wasn't necessary, but would be nice to have if I ever wanted to race it a bit, My thing on it is to do everything once and not have to go through it again. Do you guys recommend this?

I am probably going to see if I can grab a good set off jugs off a 1000 and bore it to 1075 to replace the 900. Anyone got one lying around???

Probably going to go with Weisco pistons and a local builder order them and bore the jugs. He said he orders the rings with the specific gap needed, so I figured it might be best to go ahead and let him order them and bore the jugs to get everything just right.

On top of that, I was considering having the heads sent to Larry C for some port work. Maybe having him do the valve grinding? As far as the head goes, I don't know what would be a good way to go. I am wondering if I should just have everything done and replaced or if it is what I will be needing for what kind of engine I am building.

Maybe APE K410 cams?

For carbs, I was advised that some BS34 Mikunis would work great. Chances are, I am not going to fork over the money for flat slides but who knows. With that advice came the thought that I should run pods. I have always been pretty anti-pods, but is this the way to go with this setup?


I know it is a lot of questions, but I am really eager to get my hands dirty!

First off ----good job on saving the bike from the breakers. The first thing I would do is strip off all the extras, like the fairing, take stock of everything you do have that is good with a view to keeping it all. There are fewer and fewer of these bikes around and it may be that you have a (getting) rarer bike on your hands. It doesn't look too bad from the pics you posted, Can you post up the frame and engine numbers? If you are within 200 #s you may have an all original bike. Find out what you have before digging into and changing too much. Great score!!!!

Nice score. The first thing you need to do is be honest with yourself and figure out just what kind of riding you want to do before building the motor.

bluezbike wrote: First off ----good job on saving the bike from the breakers. The first thing I would do is strip off all the extras, like the fairing, take stock of everything you do have that is good with a view to keeping it all. There are fewer and fewer of these bikes around and it may be that you have a (getting) rarer bike on your hands. It doesn't look too bad from the pics you posted, Can you post up the frame and engine numbers? If you are within 200 #s you may have an all original bike. Find out what you have before digging into and changing too much. Great score!!!!

When i got the bike, i think as soon as i got it home i took off that fairing and luggage accessories. Couldnt stand the look of it! Off the top of my head, i dont think the numbers were within 200, but ill post the numbers up as soon as i can. Typjcally, i am purist when it comes to one of these types of things. This may be the one thing that breaks me from that. I certainly will not be bobbing or cafeing it.

peter1958 wrote: Nice score. The first thing you need to do is be honest with yourself and figure out just what kind of riding you want to do before building the motor.

Well that is pretty easy for me to figure out. About 98 percent would be street riding. The majority of that is highway. Thw town i live in is built around highway. Normally, i would be just fine going stock, but i think it would be fun to get some performance into it.

Found some more pics

Went over to my storage today and got the numbers. I also took some time to spray every bolt I could see on the engine with penetrating oil.

Frame# Z1F-093707
Engine# Z1E--096505

1974 Z1-A Z1F-20000 through Z1F-47499
1975 Z1-B Z1F-47500 through Z1F-85700
1976 KZ900-A4 Z1F-85701 through Z1F-13xxxx for bikes manufactured in Japan
1976 KZ900-A4 &
1977 KZ900-A5 Z1F-500001 through Z1F-51xxxx for bikes assembled in Lincoln Nebraska

peter1958 wrote: 1974 Z1-A Z1F-20000 through Z1F-47499
1975 Z1-B Z1F-47500 through Z1F-85700
1976 KZ900-A4 Z1F-85701 through Z1F-13xxxx for bikes manufactured in Japan
1976 KZ900-A4 &
1977 KZ900-A5 Z1F-500001 through Z1F-51xxxx for bikes assembled in Lincoln Nebraska

So for sure this would be a 76 KZ900-A4, right?

Making a little bit of progress on the bike.

So far, Ive got the frame stripped down. Soon I will start prepping it and the various other fun stuff for powdercoat.

Got a set of 1015 jugs from a member on here and dropped it off at a place here in AZ to get it bored to 1075. While I was there, the shop had a dyna ignition, so I picked that up as well. Still need to get the coils but it's a start.

Picked up another tank by chance last night. Looks like someone tried filling the emblems with filler, but still probably easier than the other tank I have which had the emblem srew snap off in their holes.

With the tank, I also got a nice set of mag rima with breaks. Doubt I will use them since I like the spoke rims.

So this the fun part, right?

Looks like a fine project.
If it was mine and I wanted Larry C to do the head I would call him now to form a engine game plan so you don't take any steps backwards

Dave

Some quick pics....