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Hi all
i have a 1978 US import Z650 B2, I have stripped the carbs because it always seems to run rich and was checking the specifications in the workshop manual and they don’t seem like mine, the carb slides are marked 1.5, main jets 102.5, no markings on the needle but the circlip is in the top groove, there are 6 grooves in the needles but my manual says there is only 5, the inlet bore into the cylinder head measures 26 mm, it is marked N7 X6, but I don’t know what that refers to, the pilot jets are marked 15, it has the standard air box , filter and exhaust , any help much appreciated 

They are Vm24ss. These were used on 650's which didn't have the california smog gubbins. If your lucky you have the airscrew type (on the cab side) not the fuel screw type (at the back under the bowl)
Standard jetting is 15 pilot and 102.5  mains. Needle clip should have 5 slots and the clip should be in the middle slot. 
If your clip was in the top slot you'd be running lean at anything above 3k rpm.

Edited got me slots upside down doh. 

From the info you posted all sounds correct except for the needle.  To the best of my knowledge the stock needle was a 5DL31 which only has 5 slots and would of been on the 4th slot stock.  Not sure what needle that is but a guess would be an aftermarket one.  With it set to the top slot it would of been the leanest setting it can be set for.