They're here again, moving bike in an attempt to undo the damage, maybe (4-9)
I believe the answer is:
back-pedalling
'an attempt to undo the damage maybe' is the definition.
I can't tell whether this definition defines the answer.
'they're here again moving bike in' is the wordplay.
I cannot really understand how this works, but
'bike' could be 'backpedal' (backpedalling is a kind of biking) and 'backpedal' is located in the answer.
'in' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for back-pedalling that I've seen is " Hastily reversing an action or opinion".)