Have you considered using one of Ron Herron's 'Teeter Limiting Devices'? Very little weight and what there is of it, is on the rotorhead. For those not familiar with it, it's a device that prevents the rotor from being able to 'teeter' on the teeter bolt until the rotor reaches a certain speed. It uses small weights that must overcome a spring. As rotor rpm increases, the weights fly out and allows the rotor to teeter. That's a brief explanation, it was written up about a year ago in Rotorcraft. I could not find article.