Z1OwnersClub GB

Hi all, can anyone enlighten me on this curiosity?
Parts manual says all the shells are the same part number, On the actual shells mine are marked: D4KA STD for the top ones, i.e. the caps, and D4JA STD for the bottom ones, i.e. the cylinder head.
Why the different numbers, all be it a letter K vs J.?

Question 2!
I am swapping over a cylinder head and caps of course, together with the valve gear, which has been stunningly refurbished by Buzz from a Z1B engine to my current Z1A engine. I won't be using the cams, from it or the shells, just refitting my A shells and cams in the newly refurbished head.
Assuming the clearances are ok with plastigauge is this acceptable or would you fit new shells?

Cheers!

All the shells are one size ( STD ) and the same part number for ordering but the individual shells have different numbers which just relate to batch codes.
You can mix and match them in any order you like as they are all the same dimensional wise.

zed1015 wrote:All the shells are one size ( STD ) and the same part number for ordering but the individual shells have different numbers which just relate to batch codes.
You can mix and match them in any order you like as they are all the same dimensional wise.

Thank you!