Stop yo weights from inducing chaos due to spinning without struts?

Disclaimer: I'm on KSP 1.11 so the strut disconnect option is out of the question.

I'm building a spin-stabilized kick stage and would like to use a yo-weight system to stop the spinning after burnout. I've attached two radial decouplers to the CoM of the spacecraft-booster assembly, with a hinge, telescoping piston, and a simple structural weight on the end of the piston. When I spin up the stage to about 360 rpm, the yo-weight assembly starts to clip outward, turning the spin-stabilization into chaotic tumbling. I tried locking the hinges and pistons, but this method still fails to work. How can I do this without struts (I can't disconnect them in 1.11)?