Piaggio CM102203 Carburetor Needle Valve with Seat – Vespa ET4, Liberty, and Sfera 125

The needle valve — referred to as needle seat in the official catalog — is the valve that the float opens and closes to maintain a constant fuel level in the carburetor bowl. This comes complete: brass seat with O-ring and steel needle with retaining clip. Original Piaggio spare part for 125cc four-stroke engines from the late nineties. Product code CM102203.

✓ Strengths

• Original Piaggio spare part – the same code that the official spare parts catalog indicates at position 1 of the Carburetor, Engine group diagram.
• Seat and needle together – not just the needle: the brass seat and its O-ring are included, and they are the half that is usually damaged.
• It's the first part to check when the carburetor leaks – dripping fuel, engine flooding, consistently wet spark plug: it's almost always the needle that no longer seals.
• A single code for five models – Vespa ET4 125, Liberty 125, Sfera 125 and Sfera RST 125, Hexagon LX4 and Aprilia Mojito 125.
• Costs very little compared to the damage it prevents – an overflowing bowl floods the engine and dilutes the oil.

Technical specifications

Vehicle compatibility

The list is taken from the official Piaggio/Aprilia spare parts catalog (B2B area). If you have any doubts, send us your scooter's chassis number and we will verify the correct code for you.

Who it's perfect for

This is the part for those who own a 125cc four-stroke from the late nineties that floods, leaks fuel from the bottom of the carburetor when stationary, or has a consistently black and wet spark plug. It is also the spare part for those getting a Vespa ET4 or Sfera back on the road after years of inactivity: old fuel leaves deposits that mark the needle and its seat, and until they are replaced, the fuel level in the bowl will not be correct. It costs a fraction of a carburetor overhaul and is the first part a mechanic checks.

Frequently asked questions

On which vehicles can the CM102203 be fitted?
In the official spare parts catalog, the code is assigned to Vespa ET4 125, Liberty 125, Sfera 125 and Sfera RST 125, Hexagon LX4 and Aprilia Mojito 125 4T 1999-2001. These are the air-cooled 125cc four-strokes of those years. Exact versions are in the table above: outside of those lines, we do not declare it compatible.

Does the package contain only the needle or also the seat?
Both are included, plus the O-ring for the seat. This is why this code is more convenient than just the needle: the seat and needle wear together, and replacing only one leaves play that causes fuel leakage. The float retaining clip is already mounted on the needle.

Where exactly is it located on the vehicle?
Inside the carburetor, in the upper part of the bowl: the seat is screwed into the body and the needle sits inside, hooked to the float tab. In the official catalog, it is in the Engine group, on the Carburetor diagram, at position 1, quantity 1 per vehicle.

How do I know if the needle is the problem?
Typical symptoms are fuel dripping from the carburetor when the engine is off, the engine flooding on restart, a black and wet spark plug, and suddenly high fuel consumption. When disassembling the bowl, you will see the tip of the needle marked with a ring: when that step is present, it no longer seals and must be replaced.

Do I also need to change the float?
Only if it is damaged. The float has a separate code, 478564 on the same diagram: it should be changed if it is punctured, if you hear fuel inside when shaking it, or if it is deformed. If it is intact, with the new needle valve, the level will be correct again.

How many pieces are needed?
Only one. The official catalog specifies quantity 1 per vehicle: these 125cc models have a single carburetor. The price shown refers to one piece, complete with seat, O-ring, and needle.