Piaggio 432542 Complete Air Filter Box – Hexagon 125, 150, LX and LXT

The complete Piaggio 432542 air filter housing – the filter box, or airbox – is the original spare part for the intake system of the Piaggio Hexagon in the 125, 150, LX, and LXT versions. In the official Piaggio parts catalog, it appears in the Air cleaner table at position 1 under the name AIR.CL.CASE. It is the casing that houses the filter elements and channels clean air toward the carburetor: if it is cracked or deformed, the engine will draw in unfiltered and unmeasured air, leading to a loss of acceleration and improper air-fuel mixture.

✓ Strengths

• Original Piaggio spare part – OEM code 432542, not a third-party equivalent
• Position 1 of the Air cleaner table in the official parts catalog: this is the main box body, not just a lid or half-casing
• Covers the entire Hexagon family – 125, 150, LX, and LXT using the same code
• Standard dimensions and mounts – mounts directly onto original supports, with no need to adapt sleeves or drill holes
• Restores proper air-fuel mixture – an intact airbox is a prerequisite for the carburetor to return to Piaggio's factory parameters
• Hard-to-find new part – for a scooter of this age, the original airbox is one of the most difficult parts to find in pristine condition

Technical specifications

Vehicle compatibility

Compatibility based on the official Piaggio parts catalog. Some reseller listings extend this code to the Hexagon 180: this is not information we can confirm. If your Hexagon is a Super Hexagon GTX, the housing uses a different code. If in doubt, send us your chassis number or the code stamped on the current housing, and we will confirm the correct part for you.

Perfect for...

This is the ideal spare part for anyone keeping a Hexagon on the road who finds their airbox is cracked: this often happens when the mounting points fail, when someone has used excessive force to clean the filter, or simply because 20-year-old plastic tends to harden and break at the edges. The typical symptom is not noise, but a scooter that runs poorly at low RPMs, runs lean, and won't hold an idle, because air is entering through the crack, which the carburetor cannot account for. Those who have reached this point have usually already tried to seal it with tape or silicone, only to find it doesn't hold, and have discovered that universal airboxes do not fit the Hexagon. On a vehicle of this age, an original, intact housing is one of the hardest parts to find: when it is available, it is worth grabbing.

Frequently asked questions

Are the air filters included?
No. This is the box body (position 1 of the Air cleaner table). The filter elements are codes 434363 and 434364, which are sold separately. Take the opportunity to change them at the same time, as you have to open the intake system to install the housing anyway.

How do I know if the airbox needs replacing?
The typical symptoms are unstable idle, sluggish acceleration at low RPMs, and a lean air-fuel mixture that cannot be corrected with the air screw: these are effects of unmetered air entering through a crack. Check the casing against the light along the edges and around the mounting points, where it is most prone to cracking.

What is the difference compared to the 487840 housing?
These are two different airboxes for two different series: 432542 is for the Hexagon 125/150/LX/LXT, while 487840 is for the Super Hexagon GTX 12". They are not interchangeable: if you are unsure, check the code stamped on your existing housing.

Are gaskets and screws needed as well?
They are not included. In the same table, you will find gaskets 433018 and 435328 and the hardware (259166, 018640, 006125, 012533, 013880). After twenty years, the gaskets almost always need replacing; installing a new housing on hardened gaskets means leaving the same problem open.

Can I install it myself?
You need to remove part of the rear bodywork to access the intake, detach the sleeve, and secure the fasteners. With the right equipment and experience, it is feasible; otherwise, it is a job for a workshop.

Is this original Piaggio or a compatible part?
It is an original Piaggio spare part, code 432542. There are universal airboxes and third-party sports filter kits circulating for these scooters: these are different products that modify the intake and require readjusting the carburetor.