The snag about a free ride (5)
I believe the answer is:
hitch
I believe this clue is a double definition.
'the snag' is the first definition.
('hitch' can be a synonym of 'snag')
'a free ride' is the second definition.
(I've seen this before)
'about' is the link.
(Other definitions for hitch that I've seen before include "couple" , "get a free ride" , "Yank" , "Temporary obstacle" , "Unexpected problem" .)