The developer of the soft mount is the best resource to tell you how it should behave at rest and under load. "Back in the day" when flying glow I used at least 10 different types of soft mounts over time before settling in on the Hyde mount. The Hyde mount secured the engine at two points and was both firm and allowing very limited movement. I used other soft mounts that allowed very visible movement at the lower RPMs - scary movement. But - they held and were overall secure.