Valve buckets stuck! Warped head?

I bought a used Kz550, 28k miles on it. But the previous owner never did a valve adjustment (he even messed up the oil changes)

I found that all (but 1) were .1mm too tight, all but exhaust #1 which was still fine. Well i took the camshafts off and took the buckets off. Now the exhaust buckets #2, 3, & 4 won't go back in! They start to go back in (and they were very hard to get out) but then they get stuck.

Me and a buddy were very careful not to mix them up.I can't even get 2 of them back out. Thinking it's either excessive carbon buildup in the valve guides that i can't see, or the head might be ever so slightly warped.

HELP!!! please, what can i do without destroying the soft aluminum head?

brianscott wrote:

I bought a used Kz550, 28k miles on it. But the previous owner never did a valve adjustment (he even messed up the oil changes)

I found that all (but 1) were .1mm too tight, all but exhaust #1 which was still fine. Well i took the camshafts off and took the buckets off. Now the exhaust buckets #2, 3, & 4 won't go back in! They start to go back in (and they were very hard to get out) but then they get stuck.

Me and a buddy were very careful not to mix them up.I can't even get 2 of them back out. Thinking it's either excessive carbon buildup in the valve guides that i can't see, or the head might be ever so slightly warped.

HELP!!! please, what can i do without destroying the soft aluminum head?

Spray some WD40 around the buckets. Go get yourself a valve lapping stick and try to pull them out with that.

I had a couple that were tight. I recall I used acetone to clean the top and duct tape folded over and stuck it on the top to pull. I doubt you have a warped head, sometimes they are just tight going in and out but OK when they are in.

As you said... very important to not mix them up.

Since they came out, they should go back in. You never removed the head, correct? They must go back in perfectly square or they will bind.

Carbon in the valve guide won't affect the buckets. You should be able to see in the bucket bores to see if there is debris in there. If there is, you can try to get it out with a rag.

Remember to remove tension on the cam chain tensioner before installing the valve cover.

Also, check this link for timing details on the 550.
home.comcast.net/~loudgpz/GPZweb/CamsKZZ...KZZXZR550500400.html

Don't be afraid to use plenty of motor oil on the buckets.
Once the buckets are in, make sure they can spin easily in the bores.

Also, even though it looks like you can get the exhaust cam back on with the tach drive in place, take it out. It almost always binds and you can break parts that way.

Thanks! I got them all out. Replaced the shims, now any advice now on getting them back in? I tried other lifters, but they don't fit so i assume the originals are still good.