Exhaust Yasuni R4 Derbi Black

Yasuni R4 exhaust for Derbi / Aprilia / GileraThe Yasuni R4 is a high-performance exhaust system built for heavily tuned engines with increased displacement in the 84–95cc range.Yasuni R4 performanceA precision-welded expansion chamber paired with the updated 2025 Max Pro aluminium silencer delivers a clean, uncompromising racing look. Volume and shape are designed for maximum output in the mid to high rev range, with a wide powerband. In practice, that means strong torque kicks in at mid RPM and stays solid all the way up.The system can be easily combined with most 84cc - 94cc racing cylinders available on the market.Due to the larger volume and the strong performance, we recommend that you use a larger carburetor such as the PWK 30, a big valve reed valve and a reinforced clutch to prevent clutch slip.Specifications Yasuni R4 high-end racing exhaustLow mount exhaustSuitable for 50cc motorcycles with Derbi engine such as Derbi Senda X-Treme, Aprilia SX, Gilera SMT etc.Black silencerWithout road approval