A drive system has a fixed support, a textile spindle having a whorl and rotatable adjacent the support about a spindle axis, a continuously advancing drive belt tangentially engaging the whorl, and an elongated leaf spring extending generally parallel to the belt and having a portion fixed to the support and an outer end carrying a roller bearing toward the whorl on the belt. The spring is tensioned to press the roller against the belt and the belt against the whorl. A dimensionally stable plate extends generally parallel to the leaf spring, spaced along at least most of its length from the leaf spring. A layer of energy-absorbing material is provided between and bonded to the plate and spring along all of a region extending from the support to the roller so that as the spring and plate bend the layer is subjected to shear.