Is this an early Z1 cylinder?

[malmojoe]

I've posted some pics at the bottom and I'm asking if it's an early Z1 cylinder. As far as I can see it is, but I have not seen other cylinders, except Z1a/b. Apreciate any guidance on this.

cheers

[Keefleaf]

The 903cc stamp block is different.I can send you Pics if required.
There have been pics posted before,( Admin ? ).

[tedsonthezed]

They changed the cylinders/Head gasket around Z1E-14319. I say 'around' because the service bulletin says 'Some Z1's above Z1E-14319 may not have the new cylinder and gasket'.

Here's a picture of the stamp block on a very early engine (01100). I'm sure someone else has a picture of a later one. Hope that helps.

[malmojoe]

Thanks Ted and Keith. Can you tell from this photo if this is a Z1 cylinder?

[malmojoe]

here's the photo of the back side. Can anyone tell me if it is a Z1 cylinder or one off a later model?

many thanks

[tedsonthezed]

Can't see a groove for the 'o' ring, so it looks like an earlier one.

[malmojoe]

ok I'll go ahead and get it bought. Just thought maybe the Z900 one might also not have an O ring.

cheers
Ted

[Garn 1]

The easiest way to tell an early z1 cylinder block is, as Keeleaf says, by the style of lettering of the embossing "903 cc".

The "3" of the 903 is different..
The early Z1 "three" has a small top curve and a larger bottom curve, (like the 903 picture shown by Tedsonthezed). Whereas, the later cylinder blocks have the "three" even (symmetrical) "much like a seagull flying on its side!"
RegardZ