Optimization SkeletalMesh

I removed the PhysicsAsset And performances have improved, But with the 5 LODS i put into the skeletalMesh ( which reduce the vertices number till 450) performances are definitely poorer ( 20 fps less) instead of having one single LOD of the original model ( which has 15 vertices). I really don’t understand why i have a drop on performances rather than an improvement. What am I getting wrong?