Fork springs .Question

When you buy a used bike how do you tell what springs are in the forks ? As in , original or up spec aftermarket . If they have been replaced how do I tell ?????

Would they have a number on them somewhere ?

#tag would probably know the answer to that question - I'll txt him to log in.

I read the naked Bandits (all generations) came out with stiffer fork springs than the faired versions, the naked ones being more likely to be used as street fighters and therefore to be wheelied. The faired ones were pitched as tourers and were supplied with less-stiff fork springs.  

I had a mate who had a naked one and complained about suspected stiction. The above may have been the reason.