This is the Pro Twister M5S based on the OS B2103 Type R engine. This 5-port long-stroke engine offers great power at medium-high speeds. The cooling head, the crankcase cover plate and the carburetor feature a new design. The new DLC-coated crankshaft has two tungsten counterweights for smooth rotation and better balancing. It comes with ceramic rear bearing, the 22E carburetor and an O-ring under the cooling head for reducing vibration and preventing dust from entering the engine.
This is the engine of choice of Pro Twister drivers running 8th scale truck.