Yes — Russian citizens need a visa for a tourist trip; there is no visa-free regime for tourism. Do this in advance: apply for a visa at the Japanese consulate or visa centre; check the document list and processing times on the MOFA Japan site; and don't buy non-refundable tickets until the visa is approved. For planning, use the Japan page and the 'Tokyo–Kyoto–Osaka' route, which shows the season and trip length.