Valve stem seals won´t fit?

I´m in the middle of changing valve seals as I´m changing head gaskets and I have removed the old valve stem seals and installed the first four seals (I think it was the exhaust side, not sure though). But when it came to the other side the seals I got from Z1enterprises would not fit, they seem a bit too big. So four valve stem seals fit but not the other four. The engine is 1200cc and the head is ported, is it possible that four of the valve seats are changed or something?

I know in the car engine world that sometimes they do install valves with oversize stems into slightly worn valve guides then ream the guides to fit. Not sure about these engines. It's not the valve seat though.

Does it not fit snug on the valve stem, valve guide or both?

I had a bike come into a friends shop that had different valve stem sizes.

Exhaust valves 7mm and Intake valves 8mm, on the same valve guide outer diameter?????

I can remember this clearly, as I was running parts for him and made like 3 trips before we got the right seals.

4TheKZ1000 wrote: Does it not fit snug on the valve stem or the valve guide or both?

I had a bike come into a friends shop that had different valve stem sizes.

Exhaust valve 7mm and Intake valve 8mm, on the same valve guide outer diameter?????

The seals does not fit on the valve seat, but it fits on the stem. The valve stem sizes are the same diameter, but one side of the valve seats seem to be smaller.

Sounds like someone was in there messing around.

Almost impossible to check the diameter of that guide in the bore? my caliper wants to hit side of bore before getting to guide.

I would guess all valve seals look alike and nothing sticks out. All guides look similar?

I would guess you could get different seal diameters, but what is the guide O.D. ?

Should be a 8mm stem. (My bad 7mm)

4TheKZ1000 wrote: Sounds like someone was in there messing around.

Almost impossible to check the diameter of that guide in the bore? my caliper wants to hit side of bore before getting to guide.

I would guess all valve seals look alike and nothing sticks out. All guides look similar?

I would guess you could get different seal diameters, but what is the guide O.D. ?

Should be a 8mm stem.

I suspected something like that...
I have to check the measures and see what may fit, but the stems are 8mm on both sides, but the guides are different, a bit smaller on one side and thats why the seals won't fit. The old seals had som kind of metal housing.

What head is this with 8mm valve stems on the valves? KZ900,1000,1100 should be 7mm valve stems.

When you say it's loose on the guide, do you mean you can pluck it right off with tweezers? Or do you mean it stays on but spins easily around the guide?

I use nothing but APE guides in everything. Never a problem with those.

BTW if that's your old 500, I'd love to ride it. It's been a loooooooong time since I rode one. That was my second bike.

sounds like some one has replaced the guides .......aftermarket replacement guide issue ...........

:blink: Z1/kz stems are 7 m.m.

Yep, the guides are some kind of aftermarket so the usual seals are too big - is it usual to change the guides during porting or any other king of modification to the engine?

Sorry, the stems are 7mm so the head is KZ1000.

Will give the head to the local Kawasaki dealer who will help me get correct seals!

PetterA wrote: Yep, the guides are some kind of aftermarket so the usual seals are too big - is it usual to change the guides during porting or any other king of modification to the engine?

No. I rebuilt my engine at 75k miles and the guides measured like new. They don't wear unless something is fitted wrong.

PetterA wrote: Yep, the guides are some kind of aftermarket so the usual seals are too big - is it usual to change the guides during porting or any other king of modification to the engine?

Sorry, the stems are 7mm so the head is KZ1000.

Will give the head to the local Kawasaki dealer who will help me get correct seals!

Yes they do wear depending on the material.
They are often removed during a serious porting job to make things easier, then new ones are reinstalled.

PetterA wrote: Yep, the guides are some kind of aftermarket so the usual seals are too big - is it usual to change the guides during porting or any other king of modification to the engine?

Sorry, the stems are 7mm so the head is KZ1000.

Will give the head to the local Kawasaki dealer who will help me get correct seals!

One reason to replace the guides is because of the cam choice. Stock guides are too tall for cams over .420 lift. You can start running into issues with the keepers hitting the valve seals. The APE guides are shorter on top where the seal mounts.

Are you certain that the guides haven't been rubbed by the inner valve springs and worn down? I've seen that happen when the inner springs break into pieces. Look it over really well.