So Def Films

clock your Rings!

Honda gave us 286cc... we wanted more. 😈

This build takes the Honda 300 platform to the next level with an **84mm Big Bore Kit** and a **fully ported Big Valve Cylinder Head**. If you're building a **CBR300R, CRF250L, CB300R, CB300F, Rebel 300,** or tackling a **Honda Grom 300 swap**, this install covers nearly everything you need to know.

From piston installation and ring orientation to cam timing, head torque sequence, and final assembly, we walk through the entire engine build step by step.

More displacement. More airflow. More power. 💥

🎥 Full video:
https://youtu.be/TAY4cQKvYFE

Would you build a high-revving 300... or just skip straight to a bigger engine? Let us know below! 👇

base gasket goes in!!

Honda gave us 286cc... we wanted more. 😈

This build takes the Honda 300 platform to the next level with an **84mm Big Bore Kit** and a **fully ported Big Valve Cylinder Head**. If you're building a **CBR300R, CRF250L, CB300R, CB300F, Rebel 300,** or tackling a **Honda Grom 300 swap**, this install covers nearly everything you need to know.

From piston installation and ring orientation to cam timing, head torque sequence, and final assembly, we walk through the entire engine build step by step.

More displacement. More airflow. More power. 💥

🎥 Full video:
https://youtu.be/TAY4cQKvYFE

Would you build a high-revving 300... or just skip straight to a bigger engine? Let us know below! 👇