TOPIC:

Thank you, I haven't evaluated the cylinders yet. The engine would not turn by hand initially and I didn't want to try to force it. So after I removed the head noticed some moderate rusting in two cylinders that was keeping it from moving. So I just soaked it down with penetrating the oil. Let it sit a day. Rock the crank back and forth. After 2 or 3 days it became free. Just glad to know I don't have to worry about balancing if I have to go another bore over.

Zed is by far the expert here, FWIW I agree they look like Wiseco. The ones I have are very similar in construction but a newer version so the identification on the top is different. 

Here’s an option if the bores will clean up with a .5mm cut. 

www.z-power.co.uk/piston-kit-1030cc-z1-z1000

Nice! Thanks for the link 

That's a nice tank!

Looks like later ('74 and on), long emblems.  If you remove one, you may find that there's two sets of threaded holes for mounting emblems.  The more closely-spaced holes should accept the shorter '73 emblems.

Are there any characters (date code) stamped on the bottom of the rear hold-down tab?  There's some limited documentation of those codes available.

Good Ridin'
slmjim & Z1BEBE

I'll check, I did a quick scan for numbers on it earlier and didn't notice any but now I know where to look, I'll check again.

Don't see any. Any other way to identify if it is OEM Kawasaki?

Serpentine inside seam.  Sure looks OEM.  We'll have to dig around in the pics we have access to.  Short on time this morning, so tomorrow or Monday.

Good Ridin'
slmjim & Z1BEBE

If your comparing an OEM form a reproduction just compare the weight . OEM tanks are a bit heavier

We were wrong about date stamps on the hold down tabs.

It's been a while since we looked into them.  There was an extended discussion about them on the Z1-classik forum some years ago.  Don't remember the details, but IIRC, nothing definitive ever came of the discussion.  Tellingly, there's absolutely nothing about tank code stamps in John Brookes' sixth edition Z1 Restorer's Handbook.  He's working on the 7th. edition now.  We'll PM on the classik forum & ask if he has any new info.

We pulled every Z1 tank we have.  Not surprisingly, they only muddy the waters further.

Repop green for a '73 Z1.  We bought this with a complete tankset from Z1 Enterprises when Jeff still owned it.  Nothing to see except different tab construction than Mama Kaw's.


OEM '73 Jaffa.  A spare we bought decades ago.  Still looking for the right bike to put it on.  No code stamps on the tab, but note the two holes inline with the tab..


Detail of the tank above.  We're back to holes.


Another '73 Jaffa.  This one came on our '73 rider.  Two holes missing. No code.


OEM Green 74 Z1-A that slmjim bought new.  No code. No holes.


OEM red '74 Z1-A.  Apologies for the poor pic.  This tank has fuel in it & we couldn't turn it upside down. Those aren't holes inline with the tab, they're spot welds.


OEM blue '75 Z1-B.  Holes & code stamping.


Detail of the tank above.  Holes & '1216' code.


OEM blue replacement tank produced during / after '76 with the KZ900 "outside seam"-pattern tank.


Detail of the tank above.  Holes apparently used for locators on underlying dimples.  '7H25' code stamp.


OEM red '75 Z1-B.  Code stamp & holes.. 


Detail of tank above.  '2 25' code & holes.


We'll hazard an educated guess that Coyote's tank was produced prior to '75, when stampings began.  Key word there is 'guess'.

This is arcane eyes-glaze-over stuff.  It's late. Going to bed.

Good Ridin'
slmjim & Z1BEBE

Short update, got the crankshaft and transmission inspected, had to replace two or three bearings. Case halves are back together. Honed the cylinders and painted them today. Probably get the crankcase painted tomorrow or the next day.

Quick question, does anybody know the length of the clutch push rod? Of the three motors I tore down, 83, 79, and 73, only the 83 had a clutch push rod. It's 8 mm. The other two use 7 mm but I do not know the length.

I think the “J” ‘83 push rod will be a two piece the “Z”/“Kz” is one piece.