| My thoughts (and responses I got when I asked a similar question) were that there would be no need to change the suspension settings for lighter wheels, the springs hold the bike up (support the bike's weight) and not push the wheels down (which would require less pressure if the wheels were lighter).
The strength required to hold the bike up is the same irrespective of the weight of the wheels I reckon..... its got me thinking though!!
Tim | 
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