Peugeot 103 SPX AC - Technical data
The Peugeot 103 SPX, introduced in 1987, marked a complete relaunch of the legendary 103 series and set new standards in the European moped market. Instead of a classic city moped, Peugeot clearly went in a sportier direction: the pedal drive was omitted in favor of a kick-start, the frame was reinforced and fitted with a rectangular swingarm, and the overall design took strong inspiration from racing motorcycles of the time.
The AC (Air Cooled) version uses an air-cooled cylinder with cooling fins. Compared to liquid-cooled models, this setup offers several advantages: lighter mechanics, a cleaner engine layout, reduced mechanical complexity, and much easier maintenance thanks to the absence of a radiator, water pump, and cooling hoses. Today, the 103 SPX AC is considered a true late-80s cult moped and, thanks to its robust 2-stroke engine, remains one of the most popular bases for tuning and custom builds in France and across Europe.
Technical data - Peugeot 103 spx ac engine
The 103 SPX AC is powered by an air-cooled single-cylinder 2-stroke engine producing 3 hp at 5,500 rpm. Power is transmitted via an automatic variator with centrifugal clutch, allowing efficient use of the engine’s output. In standard trim, the moped reaches a top speed of up to 60 km/h.
As with all classic 2-stroke engines, lubrication is provided by a mixture of petrol and oil (typically 2-3%), which also helps to cool internal moving parts.
- Engine: Single-cylinder 2-stroke
- Displacement: 49.1 ccm
- Cooling: Air (through cooling fins).
- Carburetor: 14mm carburetor from Gurtner or Dellorto
- Intake: via reed valve
- Starter: Kick starter
- Gearbox: Variator with centrifugal clutch
- Ignition: 12V electronic
- Top speed: 60 km/h (standard)
Chassis and components - moped Peugeot 103 SPX
The SPX chassis was designed with a clear focus on sporty handling, setting it apart from conventional urban mopeds. The tubular frame integrates the fuel tank directly into its structure, reducing weight and improving mass distribution for better overall balance and handling.
Up front, a sport-oriented telescopic fork with a larger diameter provides stable and controlled steering. At the rear, a rectangular swingarm with dual adjustable shock absorbers allows preload adjustment to suit rider weight and riding style. Braking is handled by 90 mm drum brakes front and rear, offering reliable, progressive stopping power with minimal maintenance.
- Frame: Tubular frame (center beam) with integrated fuel tank
- Front suspension: Telescopic sports fork with larger diameter
- Rear suspension: Rectangular swingarm with adjustable double shock absorbers
- Front and rear brakes: 90mm drum brakes
- Front tire: 2 1/2 x 16" (tubeless)
- Rear tire: 2 3/4 x 16" (tubeless)
- Dry weight: 54 kg
- Tank capacity: 5 liters
- Instruments: Speedometer up to 90 km/h, fuel gauge
Tuning and spare parts for vintage moped Peugeot 103 SPX AC
The Peugeot 103 SPX AC is a highly popular and versatile model within the European tuning scene. Its simple 3-transfer-port engine design makes it ideal for step-by-step upgrades, ranging from mild performance improvements to full race-level builds.
- Cylinder kits: From 50cc to 70cc racing cylinders (Malossi, Polini, Stage6...), capable of doubling stock power
- Sport carburetors: 17mm, 19mm or 21mm upgrades (Dellorto, Polini CP, Malossi)
- Racing exhausts: Tuning exhausts (Yasuni, Doppler, Stage6) with a 15-25% increase in performance
- Reinforced crankshafts: Long-stroke crankshafts for more displacement and reliability with high performance setups
- Sport variator: With adjustable weights and optimized pulleys for better acceleration and higher top speed
- Programmable electronic ignitions: For adjusting the ignition timing to the respective setup
Styling parts and customizing: Large selection of styling components such as racing handlebars, mirrors and LED lights. Thanks to its large community and excellent parts compatibility across the 103 range, the 103 SPX AC is equally suited for faithful restorations or ambitious tuning projects aimed at pushing performance well beyond stock limits.
All original and tuning parts for Peugeot 103 SPX AC are available in our online store.
