Cycling briefly towards Indonesia's capital in swimwear (6)
I believe the answer is:
bikini
'swimwear' is the definition.
(I've seen this before)
'cycling briefly towards indonesia's capital' is the wordplay.
'cycling' becomes 'biking' ('bike' can be a synonym of 'cycle').
'briefly' means to remove the last letter.
'towards' says to put letters next to each other (I've seen this in other clues).
'capital' indicates taking the first letters.
The initial letter of 'indonesia' is 'i'.
'biking' with its last letter taken off is 'bikin'.
'bikin'+'i'='BIKINI'
'in' is the link.
(Other definitions for bikini that I've seen before include "gear in two pieces" , "Beach wear" , "Skimpy two-piece swimsuit" , "Brief two-piece swimming costume" , "Pacific atoll, used for US nuclear weapons tests" .)