The wheel bearing spacer (bushing)
is necessary. It prevents side loading of the bearings; that is why all my motorcycle wheels have them.
The support ring keeps the spacer/bushing in the middle of the hub, so it doesn't slip down, making it hard to get the axle through the hub.
__________________
Spud
"Never argue with an idiot. He will drag you down to his level, and beat you with experience."
Mark Twain
2015 Zongshen ZS250GY-3 (RX3)
2006 Zongshen ZS200GY-2 (Sierra 200)
2005 Honda XR650L
2004 Honda CRF250X
1998 Kawasaki KDX220
Mods made to my Zongshen ZS200GY-2:
http://www.chinariders.net/showthread.php?t=6894