Complained about most of weight system providing security for climbers? (6-3)
I believe the answer is:
carpet-rod
'security for climbers?' is the definition.
(a carpet-rod secures a carpet that climbs stairs)
'complained about most of weight system' is the wordplay.
'complained' becomes 'carped' (I've seen this before).
'about' is an insertion indicator.
'most of' means to remove the last letter.
'weight system' becomes 'troy' (troy is a system of weights).
'troy' with its final letter taken off is 'tro'.
'carped' going around 'tro' is 'CARPET-ROD'.
'providing' is the link.
(Another definition for carpet-rod that I've seen is " What keeps stair covering in place".)