SC-Project SC1-R 2-1 Full Exhaust System in Stainless Steel for Aprilia RS 660 (2020-2024) A23A-KC90

Born on the dyno and refined on the track, the SC-Project SC1-R 2-1 full exhaust system for the Aprilia RS 660 is the direct result of SC-Project's collaboration with Aprilia Racing on the RS 660 Trofeo championship. This is not a road compromise — it is a purpose-built racing system that removes the catalytic converter, eliminates unnecessary mass, and liberates the parallel-twin to perform exactly as the engineers intended at the limit.

Key Features

• Full 2-1 system engineered for the Aprilia Racing Trofeo RS 660, delivering optimised torque and peak power across the rev range
• Header pipes fabricated from AISI 304 stainless steel with CNC-machined couplings for a precision, rattle-free fit
• T.I.G. welded throughout for race-grade strength and a clean, motorsport aesthetic
• Catalytic converter removal reduces operating temperature and unlocks additional power
• SC1-R slip-on silencer available in carbon fibre or titanium — both chosen for maximum weight saving and race-day looks
• Carbon fibre end cap and dedicated carbon heat shield included as standard
• Lambda sensor port retained for ECU compatibility

Track Performance

The SC-Project SC1-R system trims a verified 2 kg from the stock exhaust weight, dropping from the factory figure of 6.4 kg to 4.4 kg. On a 660 cc machine where every kilogram of unsprung and centralised mass matters, that reduction translates directly into sharper turn-in, faster direction changes and reduced stress on the chassis between corner sequences. The optimised 2-1 collector geometry promotes a broader torque spread, keeping the parallel-twin pulling hard from the mid-range and carrying that energy through to the top of the rev range where race lap times are decided.

Build Quality

SC-Project manufactures this system to the same standards applied to its MotoGP and WorldSBK programmes. Every header joint is TIG welded by hand, the CNC-machined stainless couplings guarantee a gas-tight seal that survives repeated heat cycles, and the carbon fibre heat shield is bonded and finished to a standard that stands up to scrutineering. The anodised aluminium single-seat exhaust bracket is included and engineered to clear the pillion footpeg hangers without modification, keeping installation time to a minimum.

Fitment and Compatibility

This system is a direct, plug-and-play fit for the Aprilia RS 660 covering model years 2020 to 2024. It is compatible with the original pillion footrests. This system is for racing use only — it does not carry road-legal homologation and must not be used on public roads.

Specifications