Bumbling tired to US city (7)
I believe the answer is:
detroit
'us city' is the definition.
(I've seen this before)
'bumbling tired to' is the wordplay.
'bumbling' indicates an anagram.
'tired'+'to'='tiredto'
'tiredto' with letters rearranged gives 'DETROIT'.
(Other definitions for detroit that I've seen before include "City in Michigan nicknamed Motown" , "Where cars are made" , "Centre of the US motor industry" , "US city associated with automobile production" , "US city in Michigan" .)