Do you only want to cycle half the distance? Take advantage of the ferry service during the season and let your bike take you comfortably to the other side of the Steinhuder Meer.
You can find information on travel times and prices here.
The Regiobus bicycle bus route 835 also runs around the sea during the summer months and offers bicycle transport by bus.
Information on travel times and prices can be found here. By the way: Unfortunately, tandems, recumbent bikes, etc. cannot be taken along. Two-wheelers with moped license plates (e-bikes or other motorized vehicles) are also excluded from transport.