I have a pair of Ritchey WCS Protocol LTD wheels and am having difficulty in finding a calliper brake block that is slim enough to engage with the machined braking surface which is narrower than normal, at 7mm/7.5mm. Standard Shimano blocks when installed to be a min of 1mm below the tyre/rim interface, hang down below the machined surface, and will in no time start to wear into the V section of the rim and will destroy the black finish and the decals. Does anyone know of a Shimano compatible cartridge brake block that has a 7mm to 7.5mm profile.