Combustion Chamber Malossi Testa Rossa D.52mm

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.

Tuning Level: Racing

We categorize our products into different performance levels  Original, Sport, Racing and High End , so that our customers can choose the right parts for their setup. It is really important to combine parts that belong to the same tuning level, this is especially true for cylinders, crankshafts and exhausts.

Racing products are designed for a more extreme uses and are developed primarily for racing. Whether you stay at 50cc or increase the displacement, the corresponding Racing parts produce much higher performance than the original parts in order to achieve maximum power.

Aluminium cylinders

Aluminium cylinders are more powerful than cast iron cylinders, but require more regular maintenance and must be combined with different components such as a reinforced crankshaft and a larger carburetor.

How to run in an aluminium cylinder?

Aluminium cylinders should be run in for about 200 kilometers , and you should use a fully synthetic engine oil.

Note: To ensure optimum performance and reliability, it is advisable to measure the squish clearance. Just have a look at our tutorial How to adjust squish clearance.