aside from having a ride like a pogo stick, the obvious test is by bouncing on it when staionary. if you can bounce on it & it jumps back up & smacks you in the ****, then it's probably hosed. if you get a nice damped rebound then it's probably okay
if you're not sure what it's meant to be like, go & bounce on a new SV in a bike shop & then go bounce on yours in the car park to compare
