...behind major report about motorcycle race (6)
I believe the answer is:
bottom
'behind' is the definition.
(synonyms)
'major report about motorcycle race' is the wordplay.
I cannot really understand how this works, but
'race' could be 'tt' and 'tt' is present in the answer.
'report' could be 'boom' (both can mean a loud noise) and 'boom' is located in the leftover letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for bottom that I've seen before include "mechanic, for instance" , "MND weaver" , "Rump" , "Least successful position" , "Behind" .)