Description
Cylinder Head Naraku 21/23, 62mm Yamaha X-Max / YZF / WR 125, racing cylinder head forYamaha X-Max, WR, YZF-R 125cc with YI-3 engines. It is a 4-valve racing head with HQ larger valves (21 / 23mm) and reinforced springs. The combustion chamber is larger (62mm) and the flow is increased. Please keep in mind that carburetor or fuel injection may have to be adjusted . the Malossi Force Master is a great solution.
Note: the cylinder head is not suitable for original or other standard cylinders, only for Big Bore tuning cylinder like Naraku NK600.74, Polini 166.0101, Malossi M.3114852 and other cylinders with 62-64mm bore.
- combustion chamber: 62mm
- intake valves: 23mm
- exhaust valves: 21mm
- for Yamaha X-Max, WR, YZF-R 125cc with YI-3 engine
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: Original
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.
Under Original you will find parts whose performance and technical specifications are identical to those of the stock part.
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.
