Description
Malossi Testa Rossa 100cc cylinder for Derbi
There is no replacement for displacement
Malossi takes its iconic Testa Rossa kit to the next level with this 100cc cylinder with 47mm stroke, developed exclusively for Derbi engines. The kit offers extreme power, reaching over 32 hp at 14,000 RPM on the dyno.
malossi testa rossa - Maximum power for the race track
This cylinder was developed with the latest Malossi technology and features 7 transfer ports to optimize intake and gas flow. In addition, the combustion chamber insert for the modular Testa Rossa cylinder head has been redesigned to further increase compression and maximize performance.
The cylinder has a closed deck structure that guarantees maximum stability and thermal stability. The Testa Rossa cylinder head enters the combustion chamber and protects the nickel coating from possible detonation. In addition, the exhaust port has been optimized to improve engine performance and responsivity.
100cc Derbi testa rossa cylinder - installation and setup
To install this kit, the crankcase must be milled to fit a crankshaft with a longer stroke (47 mm) and longer connecting rod (100 mm).
It is recommended to add the following components to maximize performance:
- Malossi crankshaft with 47mm stroke (Ref. M5318895).
- Malossi exhaust (Ref. M3220038). This exhaust is fixed to the cylinder with 3 screws and an O-ring to ensure a perfect seal.
- Carburetor at least 30-34 mm
- VForce reed box / Malossi MHR reed valve or other racing reed valve
- Reinforced clutch
technical data testa rossa 100cc malossi:
- Complete cylinder kit: Malossi Testa Rossa cylinder with modular cylinder head, 1-ring piston with piston pin, rings and piston clips, gasket set, stud bolts, parts required for assembly
- Cooling: Liquid-cooled
- Transfer ports: 7
- Material: Aluminum
- Bore: 52 mm
- Stroke: 47 mm
- Connecting rod: 100 mm
- Displacement: 100 cc
- 1-ring piston with 14 mm pin
- 2-piece cylinder head
- Compatibility: Derbi Euro 3 & 4
ATTENTION: 100cc displacement can only be achieved with a 47mm stroke crankshaft and 100mm connecting rod. This cylinder is designed to operate ONLY under these conditions. We actively recommend that you opt for the corresponding Malossi crankshaft!
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.
How to Install a cylinder on a scooter, motorcycle or moped
The cylinder or cylinder kit is the heart of the engine on scooters, motorcycles and mopeds. It consists of a cylinder, a piston with piston ring(s), a cylinder head and gaskets needed for installation.
The service life of a cylinder depends on whether it has been fitted correctly.

Tuning Level: High End 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.
High End Racing products are exclusively designed for racing and should only be handled by tuning pros with the appropriate technical know-how. High-end racing parts often require modifications or machining of certain elements to accommodate the often larger components (larger crank webs, larger intake, etc.). Whether you stick with 50cc or increase the displacement, high-end racing parts offer much higher performance than the original parts and are the most powerful tuning parts.
Note: To ensure the reliability of the engine, it is important that the parts are compatible and that you do regular maintenance on your two-wheeler.
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.