Holiday, perhaps, going to urban cycling hub? How quickly can you get away? (6,8)
I believe the answer is:
escape velocity
'holiday perhaps' is the definition.
The definition and answer can be both related to time as well as being singular nouns.
Maybe you can see a link between them that I don't see?
'urban cycling hub? how quickly can you get away?' is the wordplay.
I cannot quite understand how this works, but
'urban' could be 'city' and 'city' is present in the answer.
'away?' could be 'a' (abbreviation as used in sports fixtures) and 'a' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
'going to' is the link.
Can you help me to learn more?
(Another definition for escape velocity that I've seen is " Speed needed to beat earth's gravity".)