The Rotax Max cylinder head is an essential part for Rotax karting engines. If part number 20 bursts, we strongly advise you to have the cylinder head replaced by a professional. This crucial component ensures optimum performance and enhanced reliability for your engine. The Rotax Max cylinder head is also known as the combustion insert and is compatible with various Rotax engine models, including the Rotax Micro Max, Rotax Mini Max, Rotax Junior Max, Rotax Max (Senior) and Rotax DD2.