74 kz400 dream/nightmare

ok guys this is where i'm at with my 74 kz400. So I paid to much for this thing, thought i could get it running for a couple of hundred bucks. IE clean the carbs, replace the spark plugs etc. basic stuff...only to find out I had zero compression and had to do a top end rebuild/repalr (new gaskets, clean and lath the valves, replace piston rings).. So now I'm sort of at a point of now return.... do i keep pouring money into this thing or just say "it's not worth the time and money, buy something that runs".. these thoughts keep running through my head. i really like this bike but when do i say when? I have the feeling I'm going to get the top end good only to find the bottom end is in dire need of repair. Is there anything I can do to avoid this bottomless pit....like a quick bottom end check? I don't know, I just feel this is a never ending repair and replace project... I don't even want to tell you what I've gone through just to clean rejet and reinstall the carbs... Just finding carb boots for a 74 is a nightmare in itself.. I guess i'm looking for words of encouragement or words of caution. When do I say when? i just want to get this thing on the road at this point... but I don't want/ can't spend 500 more dollars to do it.. What do I do?

Ive still got that 400 motor,if all else fails you might be money ahead just to find a good running 440 motor and find out what it takes to stuff it in there.
Theres plenty of 440s out there,easier to get parts for I would bet.
When you take into consideration how far that little 400 will go on $5.00 worth of gas when its finished Id say its worth dumping a few $s into,not to mention all the experience youre getting! :woohoo:

Not to mention you get to hang out with all of us,A $19.95 value at no extra charge! :woohoo:

Welcome to old bikes.

Haha!

Theres always this option! :woohoo: www.cycletrader.com/listing/2013-Kawasak...nja-ZX-14R-108459212

Don't know how deeply you are into it but its such a clean 400 it would be a shame to move it on to some guy who is just going to chop it up into a bobber or something worse. I would tend to lean toward what wireman is suggesting and look for a good replacement motor.

Does anyone know if a 440 will slide right in there?

All bolt holes line up except the top one on the rocker box.

recez wrote: ok guys this is where i'm at with my 74 kz400. So I paid to much for this thing, thought i could get it running for a couple of hundred bucks. IE clean the carbs, replace the spark plugs etc. basic stuff...only to find out I had zero compression and had to do a top end rebuild/repalr (new gaskets, clean and lath the valves, replace piston rings).. So now I'm sort of at a point of now return.... do i keep pouring money into this thing or just say "it's not worth the time and money, buy something that runs".. these thoughts keep running through my head. i really like this bike but when do i say when? I have the feeling I'm going to get the top end good only to find the bottom end is in dire need of repair. Is there anything I can do to avoid this bottomless pit....like a quick bottom end check? I don't know, I just feel this is a never ending repair and replace project... I don't even want to tell you what I've gone through just to clean rejet and reinstall the carbs... Just finding carb boots for a 74 is a nightmare in itself.. I guess i'm looking for words of encouragement or words of caution. When do I say when? i just want to get this thing on the road at this point... but I don't want/ can't spend 500 more dollars to do it.. What do I do?

Compression,spark, fuel, the three things you need for an engine to run.
You have just learned one of the basic rules of things mechanical.
One of many more to come.
It's not the end of the world,most of us here have been thru the same thing.
I would suggest swapping in a 440.
The 400 can be somewhat of a nightmare with the oil leak and serviceability of the carbs.
With the 440 you get a little more power and far less problems with the carbs.
The 440 is a direct drop in except for the top mount and carb spacing.
You'll need the 440 carbs because the spacing ( distance between carb ventri center line ) is narrower.
2 questions, do you have a local bike shop that can service and or order parts?
And do you have a service manual?

Do you know what the current problems are? If you can carefully and accurately diagnose the problem(s) you may be able to repair the bike without spending time and money on items that are already within spec. Ed

yea I'm in seattle so I do have a local shop that I've been going to. And yes I do have the "original" service manual. Have been reading and using it regularly. The 440 motor replacement sounds like a good Idea... but again how much am I looking at to get one of those? Then again on the carbs for the 440? I'm feeling like I should stick this motor out for now because I've just bought a new gasket set, new rings, and have cleaned/honed the cylinders and cleaned valves and valve seats. Just going to lap the old valves as my local mechanic knew I didn't want to spend a ton of money on machining, and said the valves were't that bad and that perhaps the fuel in my cylinders was more of a result of the valves sitting for so long and being so dirty. Fingers crossed on that! thanks for the suggestions.
and yeah I guess I sort of just paid for an education! Try to look at the positives. I know a lot more about bikes now

650ed wrote: Do you know what the current problems are? If you can carefully and accurately diagnose the problem(s) you may be able to repair the bike without spending time and money on items that are already within spec. Ed

so far as the top end goes I do. But I have no idea about clutch transmission and the like. Bike has a lot of miles..didn't know 20,000 miles on a bike was all that much until i got more into it. Uhmm I'm a perfect example of the guy who purchased a motor cycle the wrong way. Didn't have it checked out... didn't know what to look for.. didn't know I was paying too much. This bike picked me. I just wanted an old bike as I've always have love the cafe style, wanted to ride, wanted to learn , but geez didn't want to be completely ripped off either. I'm bummed right now.

Don't be too bummed; consider it an opportunity to learn about old bikes. The good news is that the bottom and and transmission on KZ bikes normally are very tough and reliable. The clutch is easy to deal with if you find there is an issue and shouldn't cost much to bring back up to snuff. Do you have a Kawasaki Service Manual? Ed