Update design of the French on remoulded tyres (7)
I believe the answer is:
restyle
'update design' is the definition.
(to style in a new way)
'the french on remoulded tyres' is the wordplay.
'the french' becomes 'le' ('the' in French).
'on' says to put letters next to each other.
'remoulded' indicates an anagram.
'tyres' is an anagram of 'resty'.
'le' put after 'resty' is 'RESTYLE'.
'of' acts as a link.
(Other definitions for restyle that I've seen before include "Of hair, shape in different fashion" , "Give a makeover to" , "make a change" , "new design" , "Modify" .)