E-bikes can now be rented from the 奥入瀬渓流館敷地内 電動アシストレンタサイクル受付所 (Oirase Keiryuukan Electric Bicycle Rental Facility) which is open from 8:30-16:30. It costs 2000yen for the first 2 hours and 300yen per subsequent half hour.
The Oirase Keiryuukan is by the entrance to the Gorge--along Rte. 102 just past the Oirase Keiryuu Hotel (奥入瀬渓流ホテル). For more information, call 080-6058-5891.
(Information from the Yururira Towada website)