Rebuild 1976 KZ900 engine(PLEASE INQUIRE)

I have a KZ 900 that i turned into a cafe racer and did a really nice job on,,,, but now taht i have it all together and looking good, and after ridding it for a while, i found that the motor leaks a little oil and smokes a little out of the right side pipe, i was wondering how much it would cost me to get the motor totally redone, or what would a couple of alternative be????

Are you asking about 'do-it-yourself' or having a shop do it?

timmac59 wrote:

I have a KZ 900 that i turned into a cafe racer and did a really nice job on,,,, but now taht i have it all together and looking good, and after ridding it for a while, i found that the motor leaks a little oil and smokes a little out of the right side pipe, i was wondering how much it would cost me to get the motor totally redone, or what would a couple of alternative be????

Where's the oil leak?

If not already done, would first assure valve clearances are to specs and test compression (remember to hold throttle wide open during compression testing).

Where compression is okay, perhaps the exhaust smoke is simply from needing to replace old hard worn rubber valve stem oil seals.

Good Luck!

also what are you wanting to do to it, stock or add some ponys to it

timmac59 wrote:

I have a KZ 900 that i turned into a cafe racer and did a really nice job on,,,, but now taht i have it all together and looking good, and after ridding it for a while, i found that the motor leaks a little oil and smokes a little out of the right side pipe, i was wondering how much it would cost me to get the motor totally redone, or what would a couple of alternative be????

A good rebuild with new pistons, rings, head redone on a KZ900? I'd wager it would cost at least a couple of thousand at a shop. I just did a rebuild from the pistons up on my 750 twin and it ran me about $800 just for parts and machine shop costs for the bore and valve job. I did all the labor myself.

If they are pulling the engine and splitting the case to do the bottom end, it would probably cost even more.

timmac59 wrote:

I have a KZ 900 that i turned into a cafe racer and did a really nice job on,,,, but now taht i have it all together and looking good, and after ridding it for a while, i found that the motor leaks a little oil and smokes a little out of the right side pipe, i was wondering how much it would cost me to get the motor totally redone, or what would a couple of alternative be????

If it smokes a bit at start-up then clears up, that's typically valve stem seals. If it smokes all the time and smokes MORE when you get on the throttle, that's blowby at the rings.

Get a manual and do it yourself. I have everything down but the cam install. It's all easy up to that point. Just find a machine shop that is familiar with these bikes and your good to go. Then you could always find a spare motor and tear it completely down and go with a big money rebuild and learn along the way. If you do it like the book says to it should be easy.

ok.. for clarification... the oil is leaking from the top of the jug, right under the valve cover in the front of the bike, around the exhaust outlets.. after looking at it further, if i were just to replace seals and rings, it would probably solve my problems.. and if anyone would know where is the best place to get these parts and order them from i would appreciate it

Well, speaking from a position of experience, if you are going to replace the rings, you also, at a minimum, need to hone the cylinders...and you'd be silly not to replace all those rubber camchain adjusting bits since you have it apart...this includes the camchain sprockets. Depending upon the number of miles on the motor, you also need to measure the camchain and possibly replace that. Lastly, replace the valve stem seals and lap the valves/valve seats. All parts can be obtained from www.z1enterprises.com :) And if you have not done so already, and I cannot emphasize this enough, BUY a Kawasaki shop manual (can be easily obtained via eBay).

timmac59 wrote:

...oil is leaking from the top of the jug, right under the valve cover in the front of the bike, around the exhaust outlets....

Leakage onto cylinder fins in area around exhaust outlets is often eliminated by installation of new copper exhaust gaskets.