Short motorcycle races held in Man (5)
I believe the answer is:
ratty
'short motorcycle' is the definition.
'ratty' can be an answer for 'short' (I've seen this before). I'm not certain of the 'motorcycle' bit.
'races held in man' is the wordplay.
'races' becomes 'tt' (Isle of Man Tourist Trophy races).
'held in' is an insertion indicator.
'man' becomes 'ray' (Man Ray was a 20th-century artist).
'tt' placed within 'ray' is 'RATTY'.
Can you help me to learn more?
(Other definitions for ratty that I've seen before include "Irritable (colloq.)" , "Mole's friend (The Wind in the Willows)" , "with pests" , "Irritable, peevish" , "In a bad temper" .)