ZDZ 420B4-JSR Two stroke four cylinder flat model gas engine 420ccm. Suitable for gian scale airplane models with weight over 40kg and wingspan over 4 meters. Displacement: 420ccm Weight: 15500g Bore: 52mm Stroke: 50mm RPM range 1000-8500RPM Ignition: Proc. controlled 4,8-7V Fuel mixture N95+rec.oil): 1:35 Recomm. twinblade props: Depend on reduction gear ratio Recomm. threeblade props: Depend on reduction gear ratio