Best shocks for street performance?

well Knackered means no longers useful as in worn out and broken

Knackers is a slang term for testicles

so i guess there is probably a link between the impact of being kicked in the..... erm.... knackers, and the state you are in for minutes thereafter, and use of knackered to describe something that is past its best or at least rendered useless

:)

i should remember where i am... apologies

Dave