Not only on the Body Cylinder & Forged Piston, changes to the engine internals are also present on the Head Cylinder, which now can produce a higher compression ratio, becoming 11.6 from the previous 11.2. This improvement comes from a more compact dome capacity size. In addition, the changes to the Head Cylinder design are accompanied by changes in the design dimensions of the valve head diameter, which becomes larger.

The LEXi LX 155 engine has a shorter Crankshaft size than the previous LEXi, which is 277.8 mm compared to 283.8 mm, as well as smaller dimensions and lighter weight of the Rotor Assy, which is 1,130 gr compared to 1,250 gr. The efficiency in terms of size and weight of these components has an impact on the motor's acceleration, which becomes better.

The Camshaft section of the LEXi LX 155 engine also received a touch of renewal. If previously the pin dowel, which functions as a sprocket cam chain holder, was made separately, now it becomes one unit (built-in) with the Camshaft. The effect is that it becomes more rigid, resulting in minimal friction.

One of the most significant changes in the latest generation Blue Core engine used by LEXi LX 155 is in its tensioner. If in the previous generation engine the gate stopper (the cushion to press the timing chain) was only pressed by a lever, this time the compression process is done by combining the lever and oil, or called Hydraulic Tensioner. The use of Hydraulic Tensioner makes the engine performance less vibrating and the sound smoother.

The last significant change is the new oil path. In the previous generation Blue Core engine, the oil path was only for lubrication in the Cylinder Head and Cylinder Body, but now it is also added to the Hydraulic Tensioner. With this new oil path, the Crankcase design becomes different from other Blue Core 155cc engines. Report by Siti Nur Arisha.