Motorcycle engine repair Aprilia RS125/3 (1998-2005)

Exhaust pipe removal
Torque wrench settings: Screws (1-2): 22 Nm (2.2 Kgm) Screw (3): 20 Nm (2.0 Kgm) Remove both side fairings; see 7.1.2. Remove the fairing air dam; see 7.1.3. Unhook the two springs from the exhaust flange on the cylinder. Release and remove the...

Engine general information
Type 2-stroke single-cylinder engine with intake reed valve. Separate lubrication with variable-rate automatic mixer (1.0 - 3.0%). Cylinders 1 Total displacement 124.82 cu cm Bore/stroke 54 mm / 54.5 mm Compression ratio 12.5±0.5 : 1 Starter...

Components that can be removed with the engine installed in the frame
The parts listed below can be removed leaving the engine in the frame. Left side of engine Clutch cover Mixing pump Coolant pump Balancing shaft gear Kick-starter (where fitted) Clutch Central area of engine Carburetor Radiator Exhaust pipe Cylinder...

Engine removal
Read 1.2.1 carefully. Torque wrench settings: Bolt (1): 10 Nm (1.0 kg·m) Sprocket cover screws (3): 5 Nm (0.5 kg·m) Engine rear mounting bolt (11): 22 Nm (2.2 kg·m) Engine front mounting nut (12): 50 Nm (5.0 kg·m) Front upper nut (13): 50 Nm (5.0...

Installing the engine into the frame
Read 1.2.1 carefully. Torque wrench settings: Top engine nut (1): 50 Nm (5.0 kg·m) Front engine nut (2): 50 Nm (5.0 kg·m) Rear engine bolt (3): 22 Nm (2.2 kg·m) Sprocket cover screws (10): 5 Nm (0.5 kg·m) Screw (13): 10 Nm (1.0 kg·m) Caution! Handle...

RAVE valve specifications
The RAVE exhaust valve is operated by a solenoid via a Bowden cable. The engine control unit operates the solenoid within a predetermined range of engine rpm. The ECU uses primary circuit frequency to calculate engine rpm. Note. The RAVE exhaust...

Exhaust valve removal (RAVE)
Read 1.2.1 carefully. Torque wrench settings: RAVE valve screws (2): 10 Nm (1.0 kg·m) Remove the fuel tank; see 4.1.1. Remove the battery and battery box mount; see 7.2.1. Partial removal Slip off the dust cover (1). Release and remove both screws...

RAVE valve component inspection
Seals Check the valve stem seal (1) and the O-ring (2) (located inside the valve housing) for wear or damage. Exhaust valve Remove any combustion residue from the exhaust valve (3) and the valve duct in the cylinder. Check the valve for wear or...

Exhaust valve installation (RAVE)
Read 1.2.1 carefully. Torque wrench settings: RAVE valve screws (1): 10 Nm (1.0 kg·m) Remove the fuel tank; see 4.1.1. Remove the battery together with the battery box mount; see 7.2.1. When installing a RAVE valve to a derated engine, first remove...