Does anyone please know if the numbers on both  jets and slide fitted to Delorto and Mikuni mean the same and can be directly compared?

I could be wrong, but I don't think you can compare jet numbers, from one carb manufacturer to another . 

I know that Mikuni Hexagon head jets & slotted head jet numbers are not equivalent -

one is flow rate I think ? , the other type some measurement of the physical size ?

also with some jets the flow is measured in the direction fuel would flow in use, while other jets the measurement is done in the opposite direction 

you would be best to call a carb specialist

I think you will find that the number on the jet refers to its diameter in hundredths of a millimeter. eg. a number 38 is 0.38mm. This I believe is a standard that has been used since Adam was a lad. But, I stand to be corrected.....................

 

Slide number is usually the height of the cutaway in mm

Ok thank you all