valve question

So on my 79 KZ 1000 st.

I took the head off, first time doing this on a bike.
How can I test if my valves a stuck? bike has been sitting for 20 + years. I should of done a leak down test first or checked the clearances firt. but since I am new a wanted to look at the internal components to learn.

So head is off, I can;t push on the valves as It requires something like 300 psi to force it down,,anyone have another tip? Visually they do not look bent either. just carboned up.

I don't think there's such a thing as a stuck valve. It really can't happen, and looking for bent valves is fruitless. A bent valve may be only bent 1mm. Did you try adding gas to the chambers yet? I don't mean to dwell on this, but I made this same assembly error 25 years ago and after removing the head I turned it upside down, added gas and all the gas immediately leaked into the intake, so I knew I had bent all 4 intake valves. You have bent valves for sure the way it was assembled, just figuring out how many is the next step. You can dismiss the stuck valve hope, not going to get that lucky.

morhaven wrote:

I took the head off, first time doing this on a bike.
How can I test if my valves a stuck?

I don't get it. Before you pulled the head Steell, RonKZ650, and Larrycavan each advised you how to test if the valves were stuck by checking the valve clearances . Was there some reason you completely ignored their advice?

bike has been sitting for 20 + years. I should of done a leak down test first or checked the clearances firt.

Again, I don't understand. Before you pulled the head Patton advised you to do a leakdown test, but now you ask if you should have done one.

Is there some reason you ask questions, ignore the advice, then ask the same questions after it's too late to follow the advice? Do you perhaps think these folks, who have tons of experience are pulling your leg when they offer good advice? Ed

650ed wrote:

morhaven wrote:

I took the head off, first time doing this on a bike.
How can I test if my valves a stuck?

I don't get it. Before you pulled the head Steell, RonKZ650, and Larrycavan each advised you how to test if the valves were stuck by checking the valve clearances . Was there some reason you completely ignored their advice?

bike has been sitting for 20 + years. I should of done a leak down test first or checked the clearances firt.

Again, I don't understand. Before you pulled the head Patton advised you to do a leakdown test, but now you ask if you should have done one.

Is there some reason you ask questions, ignore the advice, then ask the same questions after it's too late to follow the advice? Do you perhaps think these folks, who have tons of experience are pulling your leg when they offer good advice? Ed

There was also a lot of other advice in there too, including advice to pull the head near the beginning. I don't see why you are getting so bent out of shape, the general consensus is bent valves, and the second quote up there isn't even a question, more of an afterthought. But it really doesn't matter, because at this point simply doing the gas trick should reveal if there are major problems with the valves. It's not too late for anything.

Morhaven, you should get a manual for your motor. Please forgive me if I've misinterpreted this, but it doesn't sound as though you have a lot of intimate experience with motors, and a book will help you with some basic troubleshooting techniques [some will even tell you the why's and wherefore's of them], and how things should go together. I completely understand wanting to tear in and learn, but you kinda need to understand how things work right to figure out what's wrong when it's not right.

So, along with checking valve sealing, since you've got the head off, how do the pistons look? Do they have any marks, gouges, or dings that would indicate being hit by a valve?

There might not have been any need to tear the motor down.

The point of the advice was to determine that and hopefully keep costs down.

Do yourself a HUGE favor....

Since you already have the head off... send it to one of several vendors listed on KZR such as Larry, Pit Stop, APE even a recommended local shop in your area etc....

Pending what your doing on this build, Stock compared to Performance, have a valve job accomplished regardless...

Prices will and can vary pending minor rebuild or complete rebuild with Port & Polish... If installing performance cam, (P&P) is highly recommended for increased air flow to truly benefit the cams performances.

Those seals, springs, valves, guides etc... have been in there for a long time and no telling what occurred way back when or what condition they truly are in without complete dis-assembly...

Considering the head gasket alone is $50, get it done correctly by a pro and have it checked out by someone who knows WTF they are doing.... If in doubt, Kibble White valves are ~ $20 each... Z1 has OEM valves... New OEM seals, others claim Viton seals but new for sure....

Best advice any of us can give you for this is one of those areas where w/out proper tools and knowledge a perfectly good head can and will become a perfectly good door stop....

OMR

my 10cents, since you have the head off, get a complete valve job done on it, also, mic the cyls, to see if they are still in tollerance, if so new rings and hone the cyls.
if not bore it out and new pistons.
check everything and replace the rubber parts and timing chain.
if your going to do it, do it right one time only

BSKZ650 wrote:

my 10cents, since you have the head off, get a complete valve job done on it, also, mic the cyls, to see if they are still in tollerance, if so new rings and hone the cyls.
if not bore it out and new pistons.
check everything and replace the rubber parts and timing chain.
if your going to do it, do it right one time only

+ absolutely all of this. cam and crank runout checks would be a good idea too.

Old Man Rock wrote:

Those seals, springs, valves, guides etc... have been in there for a long time and no telling what occurred way back when or what condition they truly are in without complete dis-assembly...

Best advice any of us can give you for this is one of those areas where w/out proper tools and knowledge a perfectly good head can and will become a perfectly good door stop....

very necessary, good advice.