No pros, when transported, use a tram (8)
I believe the answer is:
amateurs
'no pros' is the definition.
'transported use a tram' is the wordplay.
'transported' indicates anagramming the letters.
'use'+'a'+'tram'='useatram'
'useatram' with letters rearranged gives 'AMATEURS'.
'when' is the link.
(Other definitions for amateurs that I've seen before include "inept lot?" , "They play for love of the game" , "Non-professionals" , "sporting types" , "Non-pros" .)