Bortola hubs the bortola hubs are a direct descendent of the acclaimed bracciano hubs light fast diminutive dependable and easy to work on japanese ezo bearings keep the rolling resistance to a minimum and the straight pull spokes keep the power transfer at maximum 28mm profile carbon rim the low profile carbon rim of the bortola c28w offers the perfect mix of low rotational mass and strength pro lite have retained the traditional rim braking surface to ensure the wheels versatility tu