Coast where swimming is limited, by experience (9)
I believe the answer is:
freewheel
'coast' is the definition.
(I know that freewheel is a type of coast)
'where swimming is limited by experience' is the wordplay.
'swimming' indicates an anagram.
'is limited by' is an insertion indicator (limit can mean to contain or border off).
'experience' becomes 'feel' (synonyms).
'where' with letters rearranged gives 'reewh'.
'reewh' going into 'feel' is 'FREEWHEEL'.
(Other definitions for freewheel that I've seen before include "Go downhill on a bicycle without pedalling" , "Flee where? (anag)" , "The cyclist may" , "Coast (on a bicycle) without pedalling" , "Move (by bicycle) without pedalling" .)