I just acquired a 1983 XS400RK (Seca). Yamaha was on 400 cc twin spree back then. XS360/400 SOCH, XJ400 Maxim DOCH and my baby Seca This is the DOCH, 6 speed, counter balanced, mono shocked version. Fairly high tech for the time, but still has the charm of an aircooled twin. Similar power...