Exhausted, it is clear, by the bumpy ride (9)
I believe the answer is:
overtired
'exhausted' is the definition.
(I've seen this before)
'clear by the bumpy ride' is the wordplay.
'clear' becomes 'overt' (both can mean apparent or obvious).
'by' is a charade indicator (letters next to each other).
'the bumpy' indicates anagramming the letters (I've seen this in other clues).
'ride' anagrammed gives 'ired'.
'overt'+'ired'='OVERTIRED'
'it is' acts as a link.
(Other definitions for overtired that I've seen before include "Exhausted" , "needing sleep" , "whacked" .)