TOPIC:

I don't know much about the big bike parts. Trying to find out if this cylinder head is Z1, KZ900, or KZ1000. It has the number "62" stamped on the exhaust side next to the cam chain tunnel.





Any help would be appreciated.

I know nothing...but that looks to me like an earlier head...that's been ported, and modded for big cams.  Hopefully, you have the cam caps too.

Nessism wrote:

I know nothing...but that looks to me like an earlier head...that's been ported, and modded for big cams.  Hopefully, you have the cam caps too.

Yes, I had it ported by my local engine guy, and I cleared it for the cams. He thought it was Z1 but he said that he is no expert to ID what year etc.
I have the cam caps so no issues there. Just thought I should find out the lineage because people are bound to ask.

I don't think the "62" is factory stamping (I could be wrong) and if what's left of the black is original it's probably 73 Z1

Please post front, bottom, and side pics, pretty please.

If the vac port castings under the inlet ports are undrilled and the gallery plugs are alloy it's early Z900.

If the exhaust studs are 6mm it's Z1.  If they're 8mm it's KZ1000.

The paint condition sure looks like OEM black from '72 - '73 manufacture with expected age patina, but that's pretty subjective.

If it's a Z1 head, detailed pics of the sides, top down at the #1 and #4 plug areas at about a 45 deg. angle, and underside with a good view of the intake castings would be necessary to ascertain how early in production it is, wherein in addition to the vacuum port bosses that Zed1015 mentioned,  Mama Kaw made subtle changes in machining at the four outer stud hole areas & minor changes to the top fin castings between the cam towers above the #1 and #4 combustion chambers.

Good Ridin'
slmjim & Z1BEBE

Has to be a Z1. I see vacuum port bosses. Drilled or not is a Z1. 

It has the blank port bosses under the intake runners and alloy end plugs.

The pictures are after using some of that Eco paint stripper, it needs another application.

I will post some pictures of the fin area, ends, and bosses later today.

Here are some better pictures uncompressed.

















The head has been big valved (37/31mm) and ported to 96/73 CFM for use with .420" lift cams.

This head came on a used KZ1000 engine I bought, the barrel on it was a 903cc but it had been fitted with 1015cc pistons.

Here are pictures of the cam cover.







I ground the "+" ribs out of the inside of the cam cover.
 

My apologies to Injected.  I was mistaken (not the first time) - I took a closer look at my spare 1974 Z1a head and it is stamped "48".  So the stamping on yours is likely done at the factory.  
And that valve cover is from a 900

Cam cover I a very early version. The circle with an A inside followed by a number 1. So it matches the Z1 head. Nice stuff!