Z1OwnersClub GB

I have recently purchased two 903cc barrels, one of which I will use when I have an engine rebuild later this year. one of the barrels looks to be the same as the one I have on my Z1A with the fins being approximately 2mm thick. The other has fins which are much thinner, approximately 1mm thick and the 'MADE IN JAPAN' is cast on the bottom of the barrel instead of the top. Does anyone know what model the thin finned barrel comes from? The photos aren't great, but the difference is easily seen.

Regards

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Id say the top one with the groove for o-ring is a 76 model.

The thicker fins are usually the earlier barrels and as Zmax says, the groove for the o-ring is a reliable indication of the "later than Z1" barrels.

The early models Z1 have a different font of embossing of the "903 cc" to the later ones. The noticeable difference is in the number "3" which has unequal branches and all numbers are larger on the earlier models.

RegardZ.

Garn 1 wrote:The thicker fins are usually the earlier barrels and as Zmax says, the groove for the o-ring is a reliable indication of the "later than Z1" barrels.

The early models Z1 have a different font of embossing of the "903 cc" to the later ones. The noticeable difference is in the number "3" which has unequal branches and all numbers are larger on the earlier models.

RegardZ.

ZMAX, Garn..
Both set of barrels have the 'O' ring groove and the same '903' font.
It is the different positions of the 'Made In Japan' logo and fin thicknesses that is at question.
Is this an indication of date /model or of them being cast at different factories etc ???