why would any changes me needed?
the weight of the wheels are never on the suspension
I can answer that one!
When your tire hits a bump, the wheel is pushed upward. If your compression damping is properly set, the spring is controled as it is compressed and you should feel little in the actual chassy.
Once the wheel reaches the height of the bump, the spring unloads all that compressed energy on the back side of the bump. As the spring unloads it's stored energy, it's the rebound damping's job to control that energy.
The compression damping will not be seriously affected. However, the wheel weighing several pounds less will have a dramatic affect on the spring as it releases the stored energy. The lighter wheel will rebound at a faster rate. Thus added rebound will be needed to compensate for the excess speed!
If I didn't explain it properly, check out Andrew Trevitt's "Sportbike Suspension Tuning" available in book stores near you. He explains the use of carbon wheels and the affect they have on the suspension quite well!