Valves and valve springs

I'm not really happy with the condition of the valves that came in my 750 head so I'm looking for some new ones. Anybody know where I can get them without paying almost 200 dollars for all OEM valves? Vesrah has a listing for them but I can't find anyone that carries them. I called APE and they couldn't help either.

Also I am really not wanting to use my 30 year old valve springs in my new motor with bigger cams. I saw that Megacycle has a set and titanium retainers and Web Cams has a kit with aluminum retainers. Not sure the on which ones to get. I've never heard of anyone using an aluminum retainer before. Really nice for weight savings in the valvetrain but I'm kinda leary about the strength, don't want the keepers pulling through or anything. Which would be the best to go with?

cant your stock valves be ground?i wouldnt jack with fancy retainers and keepers unless you are going racing.have you measured your stock springs and what does your cam manufacturer reccomend?

kxhonda wrote:

I'm not really happy with the condition of the valves that came in my 750 head so I'm looking for some new ones. Anybody know where I can get them without paying almost 200 dollars for all OEM valves? Vesrah has a listing for them but I can't find anyone that carries them. I called APE and they couldn't help either.?

There is a seller on ebay called "Rusty Riders LLC" who offers NOS valves all the time for dirt cheap (like $12 each). I got a full set from them for my old 750 twin.


kxhonda wrote:

Also I am really not wanting to use my 30 year old valve springs in my new motor with bigger cams. I saw that Megacycle has a set and titanium retainers and Web Cams has a kit with aluminum retainers. Not sure the on which ones to get. I've never heard of anyone using an aluminum retainer before. Really nice for weight savings in the valvetrain but I'm kinda leary about the strength, don't want the keepers pulling through or anything. Which would be the best to go with?

The pros at the machine shop tested the 30 year old springs in my 1979 750 (77k miles) and they said they were full strength.

Grind your valves and put out VS900K springs in it and you are good to go.

Jay

The valves are pitted from rust on the stem. IMO they're not usable.

Jay, I just called you guys today to get springs and they said they didn't have anything that would work on the 750's. Hope I can call tomorrow and add them to my order so I don't hafta pay shipping twice. Would I be able to ask for you so I can actually speak to someone who knows what they're talkin about?

I have this picture in my head of Jay walking into the office in the morning carrying a helmet in one hand and a clue bat in the other and saying "Ok, what moron said we don't have any valve springs for a Kawasaki KZ750?" :laugh:

And that reminds me, I wonder what bike Jay rides?

kxhonda wrote:

The valves are pitted from rust on the stem. IMO they're not usable.

You might want to let the machinist check them. The sides of the stems actually have almost no thrust on them in use, so a little surface pitting won't do much of anything as long as the major diameter of the shaft is not changed.

Even if the shafts have a bit of wear, I understand the valve guides can be worked to snug them up.

Even if the shafts have a bit of wear, I understand the valve guides can be worked to snug them up.

Is anyone still knurling valve guides? I thought that practice ended at the same time as knurling pistons.

kunrling guides is a cheap fix that dosent last very long,, also you cannot knurl bronze or high quality steel guides, like the bikes have, best bet is to replace them, hone the guides to the proper size and have the valves and seats ground.

He is saying that there is rust pits on the stems, I would have to see them to make the call on if they are usable or not, gut feeling is no, and replace them.
The valve will have the chance to break the head off from small stress cracks forming on the rusted area

BSKZ650 wrote:

He is saying that there is rust pits on the stems, I would have to see them to make the call on if they are usable or not, gut feeling is no, and replace them.
The valve will have the chance to break the head off from small stress cracks forming on the rusted area

That is exactly what I'm afraid of is the valves breaking cause the rust pits are right under the head of the valves. My guides are perfect. I'll go get a pic of one of the valves.

Here it is.

those are way too far to reuse, that looks like the stock two piece valve, if you are putting in a cam and springs, buy some one piece stainless steel valves, you will like them a lot better

The valve face don't look good either :woohoo:

You're right, there is absolutely no way I would use those valves.