Fork out if new bus is red (8)
I believe the answer is:
disburse
'fork out' is the definition.
(I've seen this before)
'new bus is red' is the wordplay.
'new' indicates anagramming the letters.
'bus'+'is'+'red'='busisred'
'busisred' anagrammed gives 'DISBURSE'.
'if' acts as a link.
(Other definitions for disburse that I've seen before include "Pay out (allotted money)" , "Fork out" , "Bus rides (anag) - pay out" , "Dole out on bus-rides" .)