2019-2025 YAMAHA YZ250F – DEF RACING STAGE 2 HEAD KIT

Description

This kit has been meticulously designed to address the known weaknesses inherent to the OEM cylinder head. The factory steel intake seat is particularly susceptible to chipping and failure, while the intake guides are also known to break, potentially leading to catastrophic engine issues. Additionally, the OEM valves and springs often fall short in performance and durability under racing conditions. Our comprehensive head kit effectively tackles all these critical concerns.

Port Design:

• Optimized exhaust and intake flow and velocity
• Power gains across all RPMs, with significant improvements in the mid to high RPM range
• Epoxied intake port improves strength and stability to the intake guide
• OEM intake spigot is supplied, fully port-matched for optimal performance

 Moldstar Intake Seat:

• Upgraded to Moldstar 90 Valve Seat Material
• No more valve seat chipping!
• Increased durability and performance
• Improved heat transfer from valve to seat improves performance and durability

 Valve Springs:

• Upgraded to Pro Circuit
• Stiffer springs prevent valve bounce which helps prevent valve and seat damage
• Accommodates a higher rev limiter and more aggressive cam profiles

 Del West Valves:

• CRN coated titanium construction
• Improved valve shape increases airflow
• Incredibly durable
• Allows higher rev limit

 Core Options: Please select one of the following options:

• Customer Providing Cylinder Head Core: $2200 (includes us working on your provided OEM cylinder head core)
• Dynamic Providing Cylinder Head Core: $2000 + $850 (includes us supplying a new cylinder head core)

Important Disclaimer:
We only provide NEW cylinder cores and will not supply nor perform exchanges on used cores. This policy ensures that the quality of our heads remains 100% for our customers.

Turnaround Time:

Customer supplied core: Estimated 3-5 weeks from the date we receive the head.

Dynamic supplied core: Estimated 3-5 weeks from the order date (we often have these heads in stock, please check with us).