Ultimate M5S Ceramic .21 engine

The new M5S from Ultimate is based on the OS B2103 Type R engine, a 5-port long-stroke engine that offers great power at medium-high speeds. The cooling head, the crankcase cover plate and the carburettor feature a new design, while the new DLC-coated crankshaft has two tungsten counterweights for smooth rotation and better balancing. It comes fitted with a ceramic rear bearing, the 22E carburettor and an O-ring under the cooling head for reducing vibration and preventing dust from entering the engine.

Source: Modelix [modelixracing.com]