We are proudly announcing O.S. SPEED R21GT for a relatively new category 1/8 GT class. The new engine aims at IFMAR world championship to be held in the United States in January, 2020. So the design of the engine is fully conformed to IFMAR regulation. The crankcase is modified version of R2101, cylinder/piston is new design: 5 scavenging ports + 3 exhaust port, the crankshaft is also newly designed: double counter weight made of Phosphor bronze for better torque, of course the crankshaft is DLC coated to minimize mechanical friction and with silicon filler for light weight. The carburetor is also new design, 22E(B)GT double adjustment type carburetor for smooth and better response from cornering with a 7.0mm restrictor, which conform to IFMAR regulation. The cooling head is designed to optimize heat dissipation and light weight.
Piston & Cylinder
5-scavenging port + 3 exhaust port design is conforming to IFMAR regulation
DLC coated, Silicon filler, double counter weights for powerful torque and response
New carburetor 22E(B)GT: Double adjust type, smooth acceleration from cornering