  The twisted suspension of a manifold is obtained by surgery along the fibre
of a principal circle bundle over the manifold. It generalizes the spinning
operation for knots and preserves various topological properties. In this
article, we show that Riemannian metrics of positive Ricci curvature can be
lifted along twisted suspensions. As an application we show that the maximal
symmetry rank of a closed, simply-connected Riemannian manifold of positive
Ricci curvature is $(n-2)$ in all dimensions $n\geq 4$. Further applications
include simply-connected 6-manifolds whose homology has torsion, (rational)
homology spheres in all dimensions at least 4, and manifolds with prescribed
third homology.
