PSR 00-01351-22 Air Injection Smog Block Off Plates for Yamaha

The PSR 00-01351-22 Smog Block Off Plates are a precision-engineered solution for eliminating the Air Injection System (AIS) on compatible Yamaha motorcycles. Designed for closed-course competition use, these block-off plates seal the air injection ports on the engine, preventing the introduction of fresh air into the exhaust system.

Why Block Off the Air Injection System?

On modified sportbikes, the factory air injection system can cause backfires in the headpipes and muffler. Unburnt fuel from modified fuel mapping, combined with the additional oxygen introduced by the AIS, can spontaneously combust in a high-heat environment. These block-off plates eliminate that risk. Additionally, on late-model EFI motorcycles equipped with O2 sensors and fuel management systems such as a Power Commander with Autotune, the air injection system must be blocked off to prevent skewed sensor readings and ensure accurate air-to-fuel ratio tuning on the dyno.

Key Features:

• CNC-machined from high-grade aluminum for a precise fit and reliable seal
• Safely blocks and seals air injection ports to eliminate AIS-related backfiring
• Reduces weight by allowing removal of associated AIS valves and hoses
• Enables accurate air-to-fuel ratio measurement on the dyno for proper tuning
• Kit includes all necessary block-off plates and airbox cap

Note: For closed course competition use only. California Prop 65 Warning: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.