Trousers for some changing gear? (5,7)
I believe the answer is:
pedal pushers
'trousers for some changing gear?' is the definition.
I can't judge whether this defines the answer.
'trousers for some changing gear?' is the wordplay.
'trousers' becomes 'pedal pusher' (pedal-pusher is a kind of trousers).
'for' means one lot of letters go next to another.
'some changing gear?' becomes 's' (I can't explain this - if you can you should believe this answer much more).
'pedalpusher'+'s'='PEDAL-PUSHERS'
Can you help me to learn more?
(Another definition for pedal pushers that I've seen is " Cyclists -- women's calf-length trousers".)