is my motor blown?

ok here we go again. the guy i have looking at my bike told me that my motor is a 900cc, not a 1000. the #'s on the motor are KZT00A048145. but he said in the cylinder it says 903. he said its a 900 is he right?

another thing. he did a compression check....this is the #'s for each cylinder...1-40 2-45 3-30 4-45

he told me my bike is basically ganna cost me a shitload of money for the top end and that i should just part it out.


please tell me he is wrong!!!!!

he is wrong

The decision is your to continue with the bike. 900 sounds like it.
That low compression means a couple of things, looking at the condition from your pictures, there would be corrosion in the cylinders and on the valves. If you get to where there will be fuel and spark, it probably won't start by kicking, or electric starter. It would probably need to be tow started, where you put in say second gear with the clutch in then release when at about 10 mph. Soaking first with ATF down the cylinders, and turning it over with the plugs out will help some.
We had a old buick that sat in a field for a long long time, had same thing really low compression. We poured ATF down its throat while cranking with the plugs in, then some gas, when it fired it made a 2 stroke look like a modern Hybrid. But it ran, then after running for 1/2 the day, it would re-fire on its own. Retested the compression, cold another day, and it had come up substantially. The car was sold as a running parts car.

trianglelaguna wrote:

he is wrong

ha ha ha...well he DID say please.

Yes,that's a 900 and NOT a 1000.

Ya those numbers are not good at all.
I've never HEARD of a 4 cylinder motor with ALL the cylinders that low! What are the chances of that?
Ask him if he had the throttle wide open while he was turning it over,doing the compression test.
And find another compression tester and do it again.
I have to wonder if the timing chain is out or something...those are low numbers,wholly.:huh:

trianglelaguna wrote:

he is wrong

ABOUT WHAT?

if its a 900 why would people say on here its a 1000?

mutherfucker, this is really a bummer!!!!

you are on a site dedicated in it's entire scope to buying,owning,and riding kawasaki air cooled bikes from the 70's and early 80's...there is nothing that ever came outta a kawasaki shop during those years that you can not get an answer to here and there is volumes of stuff that came after through peoples desire to build,hop up, or just improve these old bullet proof bikes...folks here have started with way worse than you have and are now riding the best bikes ever built...the kawasaki you have is the best bike ever built and any problems it may have can be easily fixed with the simplest of tools...folks here will be there for you too...so often some normal person says that will cost you thousands....while someone here says...aha now i know why i've been keeping that extra part laying around...and sends it to your door.....

these bikes will stop traffic and bring folks from the other side of a parking lot to sit and talk about "their kz back in the day"....

you own "THE" muscle bike of that era,the bike that won more classes of chapionships and more races than any bike ever made...from hill climbs to the corkscrew at seca it won many many titles...

folks who rode your bike to race wins..went on from there to become world champions...and still talk fondly of racing KZ's with giant smiles on their faces..

no it aint "blown"

kz1k wrote:

trianglelaguna wrote:

he is wrong

ABOUT WHAT?

Pretty sure he was ribbin ya,cause you said,"Please tell me he's wrong".

And even if you DID have to rebuild the top end,it might not be a SHITLOAD of money.Depending if the valves got bent,you might just be looking at a gasket set and some cleaning,maybe new rings.
But like I said,borrow a compression tester that you KNOW is giving a true reading(calibrated properly).

do you have a "factory" shop manual....

there is a begining a set of steps to find out "if" those readings he claims to have seen are correct...i would want to do my own compression test...if it felt week when you were kicking it over...no resistance...then it may indeed have something wrong...the chances that it is a 900 are small...if the motor numbers by the oil adding little twist cap are kz1000 ,and the block under the exhaust pipes exit area has a small 1 inch stamp that says 903cc...it only means someone used a 900 block to do a bore job on ,as the 903cc...and 1015 blocks are the same where the pistons iron jugs(inside the finned block) slide into the cases of both motors and the 900 and 1000 bottom ends on those yrs were the same...so if some P.O had a re-bore they may have tossed the 1015cc block from you engine and bored a 903cc that was available to say 1025cc...or 1015cc(which the original may not have been good for now)...so the block says 903cc...but inside...who knows without see the piston imo....

even if you had to do some motor work...the "thousands " he quoted you is for his work....for"thousands "you could get a bad ass motor almost..or you could get another motor for cheap and bypass that shit for now,,,build the spare when you get the spirit.....stay on getting that harness squared away on the cheap...stay on getting it sparking and trying to start then ...ask what ever the next step is...imo

You can pop off the valve cover, check to see that there is at least some valve clearance, and the timing chain is in time. Manual will have the procedures. Might be a good idea, then if this looks good do another compression test, and add some oil, recheck.

That fellow was just trying to give you a heads up that your motor condition was not what would be expected to have a running bike.

Don't fret too much. If worst comes to worst start checking Craigslist for motors...I see usable engines from time to time for around $300.00 .

I agree with the previous poster. Get some different equipment and do another compression test to start.


Here's 4 engines I came up with in a quick search. All different prices.

Here's one: erie.craigslist.org/mcy/1928844643.html

Z1R engine: annarbor.craigslist.org/mcy/1934075621.html

Another: dallas.craigslist.org/dal/mcy/1958671071.html

Another: raleigh.craigslist.org/mcy/1895863857.html

Motor Head wrote:

You can pop off the valve cover, check to see that there is at least some valve clearance, and the timing chain is in time. Manual will have the procedures. Might be a good idea, then if this looks good do another compression test, and add some oil, recheck.

That fellow was just trying to give you a heads up that your motor condition was not what would be expected to have a running bike.

Yes,good call...maybe a P.O. who didn't know what they were doing,used too thick of valve-shims...that would make sense on the low compression readings.