Dyna-Start is a brand of belt driven starter generator. Similar setups are often seen on old garden tractors. These were common on small inboard engines.
The chain drive setup has an overrunning clutch to disconnect it once the engine is running. Gravely made these available on two-wheeled garden tractors. These usually don’t have any charging capability–but I don’t think this matters a lot unless there are other electrical loads. A healthy,fully charged battery can give quite few starts. My advice on these is to make sure the overrunning clutch is free and lubed.
Being now in my 70s the point of electric starting becomes moee obvious.
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