TOPIC:

Where you have a nice band on the valves, is there a corresponding band with no gaps on the seats ?

Oh well. I think I took some shortcuts, and not all valves had the “nice circle”, especially the exhaust ones; which are the ones with leaks.
intake are almost perfect,
with just an extremely small leak.

I will take valves off again, and insist. Can lapping be done with the valve seals in place? I fear I may just break them. 

One more question, regarding valve seals. They were really easy to get in; no tools needed, just finger pressure. They are indeed the kz1000j ones; does that sound right? I expected more “resistance”…
thank you!

cartal wrote:

Oh well. I think I took some shortcuts, and not all valves had the “nice circle”, especially the exhaust ones; which are the ones with leaks.
intake are almost perfect,
with just an extremely small leak.

I will take valves off again, and insist. Can lapping be done with the valve seals in place? I fear I may just break them. 

One more question, regarding valve seals. They were really easy to get in; no tools needed, just finger pressure. They are indeed the kz1000j ones; does that sound right? I expected more “resistance”…
thank you!


Answer
Hi  the valves look nice if i was you i would lap them more to get them sealing so the engine get max compression and good coling on the valves. Lap them several times before testing them shifting between coarse and fine paste.
About the seals yes they are easy to just push down on this engine you feel they snap into place. I just did same work and decided to change the seals because i did many attemts to get the valves to seal and had to take the valves in and out many times .I had deburred / grinded sharp edges where the red arrows points in the picture  when doing the valve job and the valveseals was only used for about 10 kilometers because i replaced them when engine was in the bike right before winter
.I decided not to take the risk reusing them and have to do the job to replace them when engine is finished and in the bike again.Replacing the seals when engine is in bike is a frustrating pain.
 Anyway it is important to deburr where the red arrow is in the picture if it is sharp edge there .If not you risk damaging the new seal when putting the valves in .
Good Luck


 

I forgot to ask if you are using the oem seals .Some bikes have upgrade seals made of viton and they have a metal jacket  .I installed viton seals on my fj1200 and that type of seals need a tool that fits the seal and more force is needed to push the seal down on the valveguide. You can also use a socket that fits . If you dont already know there is a trick to make the install of the valve keeperes much easyer.That is to use grease on the inside of the keepers or on the stem they will then stick to the stem.

Thank you both. I think I was being a little lazy, and was having high hopes from little work. I took all all springs and stuff off again, and started with left exhaust valve. It had some little tiny spots in the “bright line”. After 15 minutes of lapping with both coarse and fine paste, they are almost gone. As said, I was missing “elbow grease”. Will redo all valves until all are spotless. Some pics for reference.
yes, I am using oem seals. I will take a look at them after the valve job, and probably change them, just for peace of mind. As you say, valve comes out many times.

Cheers!

 

I hope it will reflect in valves being closed, but definitely, spending some time on each valve makes a big difference 

 

I was reading some related posts today, and realized that one set of valves is brand new. They are the ones belonging to the piston with the hole. 

As I read here: kzrider.com/forum/2-engine/619249-valve-...are-you-doing#887909

Will lapping do for these brand new valves (Vesrah from Z1 enterprises), or should I get the seats cut? 

 

If lapping produces a nice sealing ring then you are good to go

All valves are in. I just did a leak-down test a few hours ago, and the combustion chambers will remain full of fuel for 45 minutes (that´s the time I tested), with the exception of 1 of them, that will only retain some 70% of the fuel. 

I´d call that a good enough test. On to the rest of the head... and the next problem. Valve buckets don´t fit!

Of course they are the original ones, and of course I saved their original locations. They don´t fit! I remember I took them off with a magnet, so I really don´t understand how or why they are not going in.

To make things worse, I got one (the first one) 1/4 in, by wobbling it a bit (expecting the springs were not making room for it), and tapped it lightly with a rubber hammer. Now it will not come out! No matter what I do. 

Have been reading this post:  www.kzrider.com/forum/2-engine/619796-st...tappet-bucket#893449 , and I am pretty sure I have no bent valves...

Not happy...

Some pics to illustrate 

I even cleaned one of the buckets with a 600 grit emery paper. Not much of a difference

 

Are the springs centred on the valves, the buckets should just drop in with no noticeable resistance (any tighter and you will have a valve stick open and destroy a piston) is there any marks in the head from the "valve spring compressor" causing high spots in the bucket housings?

I don’t see any noticeable marks in the bucket housings. They definitely don’t fall in place. I did all valves to a cbr900rr a few months ago, and buckets were completely loose. These are really tight. 
the one I got in (and cannot get out), will spin if pushed with a screwdriver (and some force), but it’s definitely not “loose”.

I’ve tried all of them and none will fit. This is possibly the strangest thing I’ve ever seen.
no, no… I’ve double checked and I’m not mixing engine parts