IAME is the engine company with the longest and most prestigious history in the international karting scene. It is 100% specialized in engines, and it has made many innovations for the new OK and OK-Junior class engines.
The most famous karting engine company in the world has managed the transition to OK engines using all its know-how, changing practically every single component. Following the flow of air and the mixture, from the reed valve pack inlet to the exhaust outlet, we can see all the Iame changes.
Let’s start with the OK class.
The first change can be seen in the reed valve pack: the spacer is made of resin rather than aluminium. This creates a thermal shield with the crankcase, with the objective of maintaining the reed valve pack cold: the incoming mixture does not heat and remains more compressed, benefitting the filling coefficient and, therefore, performance.
The spacer has also been made thicker and its shape has been changed. Following this, the inlet ramp from the reed valve pack to the crankcase has changed: to prevent the flow, which then goes towards the side of the transfer ducts, being “disturbed” by the air eddies generated by the rotation of the motor, IAME has realised a partially closed crankcase pump, leaving only the necessary movement of the connecting rod.
The transfer ducts have been modified in terms of volume and curvature, while the sections have remained similar.