Bike effortlessly (5)
I believe the answer is:
coast
'bike effortlessly' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for coast that I've seen before include "Not take part in (an activity)" , "Run without power" , "Diminish, lessen" , "Land bordered by the sea" , "(Of car) move without power" .)