Along the Yigal Allon Promenade, half-a-dozen operators, including Tiberias Water Sports and Water Sports Center, offer motorboat rental (100NIS for 30 minutes), waterskiing (200NIS for 15 minutes) and banana-boat rides (40NIS for 15 minutes). Closed on rainy days, cold days, Shabbat and Jewish holidays.
Parts of the Sea of Galilee are great cycling territory. Completely circumnavigating the lake (about 65km) takes about six hours. For about 70% of the way around you can follow the Kinneret Trail (Shvil Sovev Kinneret), but the rest (including from Ein Gev on the east coast to Arik Bridge at the lake's northern tip) has to be done on highway shoulders for now. Make sure you have a good (eg 1:50,000-scale) map as the route is not well signposted.
For a nice half-day ride from Tiberias, you can head 8km south to Yardenit, from where an 8km circuit follows the Jordan River.
Start early to beat the heat and take plenty of water. When riding on roads, make sure you’re highly visible and stay on the verge (shoulder), as far as possible from traffic. Do not ride after sundown.