Introduction

Aprilia - RX 125 (2018–2020, ZD4KXA00)

The Aprilia RX 125 with type code ZD4KXA00 is a lightweight, street-legal enduro motorcycle produced from 2018 to 2020. As a modern take on the classic 125 cc enduro, it offers agile handling, contemporary styling, and Euro 4-compliant technology.
Thanks to its low weight, long suspension travel, and off-road-ready 21/18-inch wheels, the RX 125 is ideal for A1 license holders looking to ride both on asphalt and light trails.

Model History

The RX 125 was introduced in 2018 alongside the SX 125 (Supermoto version) as the successor to earlier Aprilia RX 125 models. With model code ZD4KXA00, it received a complete design update, LED lighting, a new instrument cluster, and revised chassis geometry. The water-cooled four-valve single-cylinder engine was updated to meet Euro 4 and equipped with an electronic Dell'Orto carburettor. From 2021, the model was replaced by a Euro 5-compliant version with a new type code.

Technical Details

The RX 125 features a water-cooled four-stroke single-cylinder engine with a displacement of 124.2 cm³. It delivers 15 hp (11 kW) at 10,000 rpm – the maximum allowed for A1 license holders. Maximum torque is 11.2 Nm at 8,000 rpm. Power is transmitted via a 6-speed gearbox and chain drive. Top speed is around 110 km/h, depending on rider weight and gearing.

Chassis and Brakes

The frame is a sturdy steel double-cradle structure with a central reinforcement. At the front is an upside-down fork with 240 mm travel, and at the rear a monoshock swingarm with 210 mm travel. Braking is handled by a 260 mm wave disc at the front and a 220 mm disc at the rear. A Bosch ABS system with rear deactivation is standard. The off-road tyre sizes are 90/90‑21 front and 120/80‑18 rear.

Colour Variants

The RX 125 was available in sporty designs such as black-red, grey-yellow, or racing graphics with number plates. Graphics and decal details varied by model year and market. Many owners customised their RX with handguards, enduro mirrors or accessories like exhaust systems, skid plates, and luggage racks.