major problems

75 z1. Bike was running 2 yrs ago when i broke the motor down.
I broke the bike down because my 2nd gear needed to be replaced and I started to hear the cam chain. the cam chain
had started to stretch. I had previously only broke down single over head cams. I figured it wouldn't be too different. the following spring I replaced the transmission,cam chain,and switched casings. then started putting the motor back together. when i got to timing the valves this was pretty much the new part. I did just what the manual said to do. now what i thought was a piece of cake
has turned into my nightmare.

After i got the motor reassembled I tried to start it with no luck. this is where I started doubting if I did it right
so i called a friend who had done this before to time the valves. I checked to see if he did it like I did and he did. the bike still didn't start. everything other than the motor I knew was right I checked and rechecked everything. the motor was the only thing that I was unsure of but after having my friend check I was more confident I was doing it right. still no luck so now I was wondering did my friend do it right. my thoughts were if we were both doing it right something had to be wrong with some of the parts but the motor ran when I took it apart. so I didnt know what could be bad. I took the motor back apart took it to the mechanic that had replaced a valve for me some years back when I first got the bike. everything checks out fine. so now I'm back to thinking maybe I misread the book and didnt time the valves right. here comes the major problems I started counting the 28 links from the arrow instead of the one above the arrow. the bike still didnt start. after repeatedly trying to start I got fed up and called the mechanic over to watch and see where im going wrong.

By now I had switched back to counting 28 links starting above the arrow. when the mechanic gets there I let him time the valves and try to start it with no luck. so we ran a compression test and realized I was not getting enough compression. he told me I probably bent a valve so I took the head and jugg off took them in the house and put them up. by now it was this last past winter. I didnt really have the space to work on the bike so I got on the internet and started to do my research. while I was waiting for this spring to come I looked over kz rider so many times it was pitiful. so now I was thinking I'm ready,I got it, I can do it but I still had a couple of bent valves. I called the mechanic up asked him to show me how to replace the valves because I wanted to learn how myself. he said o.k. so I went over to his house with the head and valves and instead just dropped them off since he was gonna do it for me for next too nothing.
After I got my head back I figured all the studying I did I was ready. put everything back together just knowing it was gonna start and I had my stomach ripped from me again. nothing. she wont start. after checking everything else and I thought to check for compression. I cant find my book so I wasnt sure if I did my compression check right but I wasnt getting much. I'm not sure if did it right 1 and 4 was only reading around 50 to 60 and in 2 and 3 I wasnt getting any. the valves I had replaced were the 1 and 4 meaning last summer 2 and 3 had good compression but not any more. now I dont know if I'm doing something wrong or it is some parts. I really truly believe that I'm doing everything right. I need advice as to my next move its been 2 yrs since I rode and I dont want to miss summer any help is greatly appreciated


a little help on choosing between 2 colors is needed

this was supposed to be the 2nd color

Really sorry about all your headaches. I'm surprised you could bend valves being only one link off, but I guess it's possible. Hope you can get it squared away.

this was supposed to be the 1st color

If it's any consolation, crap happens on these old bikes. I had to rebuild the engine on my 750 a few years back and it went south: after I reassembled it (and it ran great) the cylinder base gasket disintegrated and it let the cylinder shift and I suddenly had a bike with no compression and no running. I had to pull the whole top end off and replace the gaskets, and I broke a piston ring trying to put it back together. The end of the story: it runs great now even though I had to do it TWICE....:ohmy:

bountyhunter wrote:

Really sorry about all your headaches. I'm surprised you could bend valves being only one link off, but I guess it's possible. Hope you can get it squared away.

I know I didnt think that it would do that either being off 1 link but my head was fine. you got it right though a headache to the point I thought about selling and believe me I love my bike.

thx bounty I know I'm trying my best not to let it get to me. I wish it was only my second time. I've done it so many times now. thats what's making me think something else is wrong but I just don't know what.

Before you pull the top off again do a leak down test, your mechanic friend should be able to do this. Now after this you can be sure if its in the head. Recheck all valve clearances, if a valve is bent the clearance will have increased from the setting. Get a full valve job done if so, make sure to either do a vacuum test or at least a solvent check on the valves after the valve work. Don't neglect the valve guides, and make sure that you have shims to reset the clearances. Then I would re-ring it so both the head and the bores are freshly sealed. When reassembling, after valve timing, rotate the motor twice by hand and recheck timing. It should rotate freely, then use your starter or kick starter to re-perform A compression test. Once verified all 4 pump up you should be confident the mechanical part of the equation is right.

before I put the head on I flipped it over poured gas on the valves and they stayed full. I stuck my finger in the intake and exaust holes and my finger was dry. I then reshimmed 1 and 4 because those are the valves I had work done on. I'm gonna take the head back off just to make sure
no more damage has been done.after I checked for compression
I wanted to do a leakdown test but didnt know how so I have to wait on a friend.
I did notice that on the back of the motor between the head and jug where the head gasket is a open space thats just didnt seem like it was supposed to be open.it seemed like air could excape. I dont remember if my old casing or any other had this same space?
thanks alot cause I need direction of what could be wrong and needs to be checked.

Head Gasket space? Don't pull it down until you do a leak down test.
Do you have an air compressor? Or a portable air tank?
An easy way to test for a major problem is to put air pressure into the spark plug hole with each piston at Top Dead Center with it on its firing stroke. If it leaks a lot of air out try to determine where, it maybe from the Gap in the Head Gasket you are wondering about. But you said something about only re-shimming the valves you replaced? What about the rest?

I checked clearance in 2 and 3 and they were fine.since they hadn't been touched I thought that was o.k. I do have an air compressor so I will do that next. that space really seems wierd and I was wondering if it was something I could do to make sure it was air tight. everything is flush all around then comes that space. so I will shoot air in and see.thx

Are you replacing the head gasket when you put the head on? The head gasket should only be torqued once, if you have intalled the head multiple times maybe you need new head gaskets. Leakdown test will find out if this is the problem.