JetPrime SLS/AIS Block-Off Plate for Aprilia RS 660 (2020-2026) – JP ES 660

The JetPrime JP ES 660 SLS/AIS block-off plate is the definitive solution for Aprilia RS 660 owners fitting aftermarket exhaust systems. Precision CNC-machined from aerospace-grade 7075 aluminium, this kit is engineered with the exacting standards and clean aesthetic that JetPrime is renowned for — removing the intrusive PAIR system entirely and replacing it with a component that looks as purposeful as it performs.

Key Features

• Eliminates exhaust popping and misfiring caused by the secondary air injection (PAIR) system when running aftermarket exhausts
• Restores a reliable air/fuel ratio for precise fuelling and optimised throttle response
• CNC-machined block-off plate from 7075 aluminium — exceptional strength-to-weight ratio and corrosion resistance
• Heat-resistant rubber caps ensure long service life under sustained high-temperature conditions
• Enables complete PAIR system removal: valve, cover and hoses all deleted for a clean engine bay
• Developed and tested exclusively for the Aprilia RS 660 (2020-2026)

Design, Finish and Heritage

JetPrime has built its reputation supplying performance engine and drivetrain accessories to serious track riders across Europe. The JP ES 660 block-off plate reflects that heritage: every surface is machined to tight tolerances from 7075 aluminium billet, the same alloy series trusted in competition-grade components. The result is a part that integrates cleanly into the RS 660 airbox, replacing the original cover and rubber cap with a single, flush-fitting plate that leaves no visual or mechanical compromise.

The PAIR system was engineered for production exhaust emissions compliance. Once you fit an aftermarket header or slip-on silencer, it becomes a liability — introducing unmetered air into the exhaust ports, disrupting the air/fuel mixture and causing the characteristic popping and deceleration misfires that undermine both rider confidence and fuelling accuracy. The JetPrime kit addresses the problem at its root rather than masking it through mapping alone.

Performance on Track

With the PAIR valve, cover and associated hoses removed and the airbox port sealed by the block-off plate, the RS 660's fuelling electronics read a clean, uncontaminated intake signal. The air/fuel ratio stabilises, throttle pickup sharpens, and the antisocial crackle on the overrun disappears. For riders running the RS 660 in track-day or race trim with a full aftermarket exhaust, this kit is a logical first step before any ECU remapping session.

Fitment and Compatibility

The JP ES 660 kit is designed and tested specifically for the following motorcycle:

• Aprilia RS 660 — model years 2020, 2021, 2022, 2023, 2024, 2025, 2026

Note: Race Use Only. This block-off plate is intended exclusively for closed-circuit track use and is not approved for road use.

Specifications