Assume that
M is a compact
n-dimensional manifold and that
N is obtained by surgery along a
k-dimensional sphere,
k ≤
n − 3. The smooth Yamabe invariants σ(
M) and σ(
N) satisfy σ(
N) ≥ min(σ(
M), Λ) for a constant Λ > 0 depending only on
n and
k. We derive explicit positive lower bounds for Λ in dimensions where previous methods failed, namely for (
n,k) ∈ {(4,1),(5,1),(5,2), (6,3), (9,1),(10,1)}. With methods from surgery theory and bordism theory several gap phenomena for smooth Yamabe invariants can be deduced.
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