Cylinder Head – Yamaha YZ125 / YZ144 (2005‑2021) / Fantic XX125 / XE125 (2021)

The VHM AA33077 cylinder head is engineered for Yamaha YZ125 across model years 2005‑2021, the YZ144 platform, and Fantic XX125 / XE125 in 2021. Crafted from high‑grade alloy, this “gold” VHM head features an improved water duct system and uses O‑ring sealing for reliability under racing loads. A standout feature is the exchangeable combustion chamber insert system—allowing riders and tuners to fine‑tune compression and combustion characteristics based on track conditions and fuel. The head body is supplied ready for use, with inserts ordered separately and engraved for identification. Pairing this head with the correct insert enables enhanced engine power, improved heat transference and greater resistance to detonation—ideal for high‑performance motocross and competition use.

Key Features / Benefits:

• Precision‑machined alloy cylinder head designed for the specified Yamaha and Fantic models.

• Exchangeable combustion chamber inserts enable tuning flexibility for power delivery and conditions.

• Improved water‑ducting and O‑ring sealing boost durability, thermal management and reliability.

• Compatible with a range of inserts to adapt compression and performance characteristics.

• Ideal for race builds, performance upgrades and serious tuning environments.

Technical Specifications / Specifications:

• Part Number: AA33077

• Application: Cylinder Head for Yamaha YZ125 (2005‑2021), YZ144, Fantic XX125 / XE125 (2021)

• Key Compatibility: Use with VHM standard inserts (e.g., AE32100‑E for YZ125/XX125; AE32100‑F for XE125)

• Features: Exchangeable combustion chamber inserts, improved water duct design, O‑ring sealing

• Material: High‑quality alloy construction

• Benefits: Enhanced engine output, improved cooling, high resistance to detonation