Exactly the opposite. In a series hybrid, there is no mechanical connection between the engine and the wheels - only an electrical one, with the battery still providing considerable power in most cases, even when it's depleted.
No hybrid ever runs its battery all the way to zero, and series hybrids are no exception. The Chevy Volt (the other notable series hybrid in Western markets) keeps its engine at a near-constant RPM by using the battery to supply torque, even when the battery is "dead." I would expect the MX-30 to do the same.
IME in several thousand miles driving/riding in a Volt, it hums away within a very narrow RPM band unless you hoon it on a dead battery in cold weather. Even then, it's not nearly as wide of a rev band as a conventional hybrid.