Look diagonally across Mission Boulevard from Belmont Park and you’ll spy Ray’s Rentals. They rent out beach cruisers, hybrid bikes, or tandem bikes. Beach cruisers are $10 a day with their online coupon. Hybrids run $40 for the day and tandems $45 for the day. Group discounts offered for a party of six — the sixth rental is free for the full-day rentals. Cycle around the corner and you’re on the boardwalk that wraps around Mission Bay. A low-impact workout, a great people-watcher activity. The 19-mile loop has only one traffic light to slow you down. Ray’s Rentals has other locations in Coronado and Pacific Beach.