Click on the technical data tab. Looks like 553 to me.
Also by the looks of it the internal nipples shouldn't make any difference to the calculation, they're just hidden by the carbon V. imagine getting a normal rim and building a carbon V which hid the nipples, the calculation would be the same right?
Bjorn - ERD is given on the Corima site http://www.corima.com/gb/produits/roues/default.cfm?family=roues_janteCorima
Click on the technical data tab. Looks like 553 to me.
Also by the looks of it the internal nipples shouldn't make any difference to the calculation, they're just hidden by the carbon V. imagine getting a normal rim and building a carbon V which hid the nipples, the calculation would be the same right?