Marchesini magnesium 5-spoke ... 6.8 lbs ... 8.7 lbs. rear
Ducati OEM aluminum 5-spoke ... 9.3 lbs ... 12.0 lbs. rear
Ducati OEM aluminum 3-spoke ... 11.5 lbs ... 13.3 lbs. rear
Ducati lightened the wheels in 1999 compared to prior years. I don't know how much, but they said so in their '99 brochures. Could be just a few grams.