Malossi MHR Cylinder Head Cover Testa Rossa

Malossi MHR

The MHR series from Malossi is generally available in 3 categories for the most popular models:

• MHR Replica
• MHR Racing
• MHR Team

The 3 model series differ in terms of performance and competitiveness. The MHR Team series includes the top-of-the-line  models with outstanding performance for racing. The MHR Racing is in the middle, and the MHR Replica adopts the basic features of the higher versions, with the emphasis on reliability for everyday use rather than maximum performance for the race track.

Malossi Testa Rossa

The Testa Rossa is the latest generation of high-end cylinders from Malossi. The series is the successor to the famous MHR Team, which has long been a reference for scooter tuning and racing. As the name Testa Rossa suggests, the cylinder head is red, which could possibly be interpreted as a small allusion to another famous Italian brand.

The Testa Rossa cylinders represent the state of the art and are extremely powerful. The cylinders were originally introduced with the C-One and RC-One crankcases, but are also compatible with original crankcases, provided they can be machined to fit the new components.

Main features of Testa Rossa cylinders

• 7 transfer ports
• Bridged exhaust
• 1-ring piston
• Two-piece cylinder head with special combustion chamber (improved water volume)

To ensure reliability and top performance, the Testa Rossa must be used with the appropriate tuning components and re-adjusted: reinforced crankshaft (racing or high-end), a suitable tuning exhaust and a larger carburetor and intake.

Cylinder head

The cylinder head of an internal combustion engine can have different shapes and contain different elements, depending on the type of engine. While in a two-stroke engine the cylinder head contains only the spark plug, in a four-stroke engine it is much more complex, as it also contains the valves, the camshaft and many other parts that are important for the operation of a 4-stroke engine.

However, these two points apply to any cylinder head:

• it must be tight
• it controls compression

Different types of cylinder heads

Each cylinder head is specifically designed for a specific cylinder. You must therefore always make sure that the cylinder head fits the cylinder.

Cooling :

The cylinder head is also partially responsible for cooling the engine. In air-cooled engines it has fins on the outside and in liquid-cooled engines there is chamber for the circulating coolant.

One-piece or two-piece 2-stroke cylinder head

One-piece cylinder heads are the most common, but modular two-piece cylinder heads are also available for 2-stroke engines. The principle is quite simple: the water jacket allows water circulation, while the combustion chamber insert closes off the combustion chamber. The cylinder head can be replaced and modified to achieve different compression ratios and thus different engine behavior.

4-stroke cylinder head

Tuning cylinder heads can also be found for four-stroke engines. Although components optimized for motocross are seldom found on the market (usually they are original components that have been reconditioned to increase performance), there are also racing cylinder heads for scooters and motorcycles. These often have optimized intake and exhaust ports and sometimes even seats for larger valves.