Riot, fret, maybe add new parts? (8)
I believe the answer is:
retrofit
'add new parts?' is the definition.
I can't tell whether this definition defines the answer.
'riot fret maybe' is the wordplay.
'maybe' is an anagram indicator.
'riot'+'fret'='riotfret'
'riotfret' with letters rearranged gives 'RETROFIT'.
Can you help me to learn more?
(Other definitions for retrofit that I've seen before include "Later adjustment" , "Modification made after manufacture" , "Add (component) not originally in place" , "Make later modifications to (equipment, etc)" , "Fit with accessory not on original" .)