1981 kz750 winter rebuild

So I picked up my 1981 kz750 LTD a few years ago, bone stock from the original owner. Here she is the day I brought her home:



Not knowing what direction I wanted to go with it, I kind of did things one by one... undid some things, redid some things, I'm sure most of you know how that goes.







Ended up somewhere around here by the end of this year.

Inspired by many of the outstanding projects I've seen on the forum as well as some underlying issues that needed to be addressed.. I decided it was time to dive in this winter and address the big picture. The motor runs really well, just passed over 25k miles this summer however I seem to have more leaky gaskets then dry ones at this point. My exhaust wrap tore along the bottom of the bike somehow and my drainplug was stripped out and dripping all year long. I was also advised that the chair is on it's last legs and I think I want to add a couple teeth to the rear sprocket.
So far my list consists of:
1) Replace Oil Pan (Already acquired one via ebay)
2) Replace any and all leaking gaskets - Suggestions welcome on what kind to use
3) Add kickstarter from a 650 (Already acquired one via ebay as well as right side engine cover)
4) Completely degrease and paint motor flat black as I have seen several members do... Looks incredibly sharp.
5) Replace Clutch and Throttle cable with shorter cables (Suggestions welcome) switching to clubman bars has left me a ton of slack.
6) I am also very interested in installing a motogaget unit, I would love to upgrade and streamline the electrical system on the bike, however this could possibly wait til next winter depending on how far I've got myself in already.

Background on me, I went to BOCES for automechanics back in high school (12 years ago) and I have some good tools but this is my first bike so the nuances are new to me. I'm really looking for any and all suggestions, no matter how obvious they may seem to get me thru this project. Another thing I would love to hear is what else should I address while I have this thing torn down... would hate to have it all together again and find out I need to tear it down again next year. I think I remember someone saying to replace a starter clutch or something while the case was split? This is stuff I would love to know.

I'm a couple hours into tear down now... Ive been bagging and labeling everything as I go. I think I'm at the point now where all I have to do is unbolt the motor and slide her out (need to recruit some extra hands)











Will all of these electric components be stripped out if I switch over to the motogadget?

Add to that list the chain and sprokets as well, I'd like to add a few teeth on the rear... Again suggestions are welcome.

Rave71 wrote: Will all of these electric components be stripped out if I switch over to the motogadget?

You'll still need things like regulator, flasher, not sure about fuse block. But whether they stay in the same place or not will be up to you. If you want to keep a stock look they can remain where they are. But one of the benefits of using an MUnit or rewiring the bike to simplify is that the components can be moved to anywhere you want them to be to clean up the the routing, the appearance, etc.

The GPZ clutch cable is shorter. I put one on my 750 with superbike bars. I also used a GPz throttle cable but can't remember the exact type. Look at photos on ebay and be sure to get the type with the proper cable ends. OEM Kawasaki cables and gaskets are the best available.

Regarding the chain and sprockets, upgrading to 530 is the way to go. Z1 Enterprises has info that should help you. Changing to a lower gear ratio will help acceleration, but the engine will be buzzy at higher speeds. Be sure you are willing to accept the compromise before pulling the trigger.

Yeah ideally I want to strip down as much of that stuff as possible and condense it in front of the battery tray... same with the fuse block on the other side. I had a pair of leather bags made up that fit right over where the original factory side covers go. Great spot to keep all the little things, clear glasses, screwdrivers, insurance and registration ect... the problem I have right now is the bag on the left side pushes out from the bike because the fuse block sticks out a bit underneath that cover.

As far as the cables, thank you for the heads up... I will pull them off and find the appropriate GPz cables... I'm looking to lose 6" of cable or so... that will really clean up the handlebars from having a big looping cable up front.

Not a big update but bringing some life back the the kirker pipes before I put the new wrap on. Using VHT header primer and paint.

So I finally got some semi-decent weather up here in NY and spent the afternoon out in the garage working. Slow going as this is my first bike, my first tear down.

I got the carb bank off, the side cover, the chain and sprockets as well as the back wheel and tire out of the way. Needed to come off anyways because I'll be changing out the chain and sprockets when I put her back together.





My next thought would be to pull off the cylinder head (Need to replace the gasket anyways) and take the motor out in two pieces. Is it possible to leave the valve covers in place and remove the whole top half as one unit while it's still on the bike? The valve covers don't appear to be leaking anywhere.

Or maybe I'm going at it totally wrong and should I just pull the whole motor out and then separate on the bench? Any tips and tricks would be greatly appreciated! Thanks in advance.

You need to remove the valve cover, take off the cam caps, remove the cam shafts and secure the cam chain so it wont fall down the cracase before the head comes off.

A manual is a necessity and will have the correct procedure

Good luck

Couple more hours in the garage today... Got the motor off the bike:



Stopped by napa to get some feeler gauges so I could check the valve clearance before I pull off the Cam Chain. I know there is a alignment process with the cam... Is there anything I should take pictures of or take note of before I take the chain off or is that just something I have to do on the way back together?

Also, this is my scratch list of things I will need... if anyone knows something I ought to get that will save me heart ache please let me know!!



Another question I have is since I'm going thru all the trouble should I replace that starter clutch while I'm here? I don't think I have had any problems however sometimes when I hold the start button nothing will happen for 20-30 seconds or I'll have to tap it a couple times before it will engage.. not sure if that's related or some sort of electrical gremlin. One of the reasons I'm tearing this down to add that kickstarter... I'd still like the push button to function tho.

I expect you will be a bit disappointed in your attempt to add the kick starter. When I wanted to add it to my 750 I was told the only way is to use the 750 top end on the 650 motor. Best of luck in your build.

From my understanding the only difference from the 650 and 750 is the top end. I have a right side cover with kickstarter hole and a kick start assembly out of an 81 650.

There are threads here on how to retrofit a kickstarter into a 750 bottom end. Seems like a lot of needless tinkering to me though.

Any time the cylinder head is removed you should also remove the cylinders and replace all the various O-rings as well as the base gasket. Kawasaki does not sell gasket kits, other than some aftermarket kits they relabeled back in the day. If you come across one of these kits stay away. These gaskets were junky and now that they have aged 35 years they are really junky now. Your best bet for gaskets and seals are OEM Kawasaki. Aftermarket gaskets range from passable quality to downright criminally poor quality. It's not worth the time and effort to use subgrade parts when working on your engine.