TOPIC:

I know this was discussed before. But what about the tiny crack in the Z1 head at the spark plug hole next to the exhaust valve seat.
Would someone buy a head with this problem on ebay? Use for a normal running engine. Not a high Performance beater.
I have this predictiment.??

Does it telegraph through to the top of the threads?
Steve

z1kzonly wrote: I know this was discussed before. But what about the tiny crack in the Z1 head at the spark plug hole next to the exhaust valve seat.
Would someone buy a head with this problem on ebay? Use for a normal running engine. Not a high Performance beater.
I have this predicament.??

Never had a problem arising from those cracks between the plug thread or between valve seats.
They are mostly on the surface and don't penetrate that deep.
Have road raced and drag raced with these cracks with no problems.
The Manzano race head that I've run on my road going Z1R for the past 18 years has some with no problems.

Yeah, a 30/40 year old head is bound to some kind of issues. I've had a hair line crack in one of my intake valve seats for 20 years, mind you it had been sitting for 15. Just put it back together, no problems yet. My other ones were stolen and this one was off a KZ 900. Seems Kawasaki cut back on quality control. Some fins weren't fully formed. Hard to tell but I can. I was disappointed to learn the smaller bikes had plain bearings not roller bearing lower ends. That and the duel over head cams and Babbitt bearings made the Z1 superior to Honda at the time.
Steve

Hello Guys. Thanks for the replies. I do have this head. I will get some pictures up later today, Thurs.
If I can get a smaller, detailed picture to show them. And some other issues. 2 exhaust studs boss' were heli arc welded a small amount and I put some heli coils in.
Yes, I myself would use this head, but it needs new valve guides and a valve grinding of course.
It would be a nice early head for restoration.

A couple months ago I asked how much a new valve seat would cost to replace. I got no answer. I am planning on buying another one budget permitting. I suspect it would be cheaper and better in the long run.
Steve

Started to take some pictures. This was a later style fin, 1973 black factory head. It has the castings for the early style vacuum nipples, but not used. This head has been sitting since the early 1990's?? When I used to drag race. I got all kinds of parts and engines, traded, given to, etc.
I fixed a couple exhaust studs way back then. Put some heli-coils in for exhaust studs.
All the fins are perfect. Nice restoration core. In my opinion.
Has the matching caps. first time taken apart. Needs exhaust guides they are too loose.
lot of meat on the valves and seats for grinding.
I am stopping here. Not going to invest that work. Won't get it out of an ebay deal.
I figure I will offer it up to the World. Early heads are getting scarse. OinkJohnson sells the hell out of them always.
But here are some detailed pictures.

z1kzonly wrote:

]

Those surface nicks hardly qualify as cracks.
They are barely scratches and nothing to worry about.