Keen to contribute to live page about hired vehicle (7)
I believe the answer is:
pedicab
'hired vehicle' is the definition.
'keen to contribute to live page about' is the wordplay.
'keen' becomes 'acid' (I've seen this before).
'to contribute to' means one lot of letters goes inside another.
'live' becomes 'be' ('be' can be a synonym of 'live'**).
'page' becomes 'p'.
'about' is a reversal indicator.
'be'+'p'='bep'
'acid' placed into 'bep' is 'bacidep'.
'bacidep' back-to-front is 'PEDICAB'.
(Other definitions for pedicab that I've seen before include "Tricycle with hooded seat at rear" , "tricycle for hire" , "with which one might be taken for a ride" , "Man-powered vehicle for hire" , "Hire-vehicle" .)