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

The Piaggio 432542 complete air filter box – the filter housing, 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 spare parts catalog, it appears in the Air cleaner diagram at position 1 with the designation AIR.CL.CASE. It is the housing that contains the filter elements and directs clean air towards the carburetor: if it is cracked or deformed, the engine will draw unfiltered and unmeasured air, leading to a loss of acceleration and incorrect carburetion.

✓ Strengths

• Original Piaggio spare part – OEM code 432542, not an aftermarket equivalent
• Position 1 of the Air cleaner diagram in the official spare parts catalog: it is the body of the box, not a cover or a half
• Covers the entire Hexagon family – 125, 150, LX and LXT with the same code
• Standard dimensions and attachments – remounts on original supports, without adapting hoses or drilling
• Restores correct carburetion – an intact airbox is a prerequisite for carburetion to return to Piaggio parameters
• Hard-to-find new part – on a scooter of this age, the original airbox is one of the hardest parts to find intact

Technical specifications

Vehicle compatibility

Compatibility from the official Piaggio spare parts catalog. Some reseller listings also extend this code to the Hexagon 180: this is not data we can confirm. If your Hexagon is a Super Hexagon GTX, the housing has a different code. If in doubt, send us the chassis number or the code stamped on the installed housing, and we will confirm the correct spare part.

Recommended products

• Filter elements 434363 and 434364 – the filters that go inside this housing: if you open the intake, it's the right time to change them
• Gaskets 433018 and 435328 – on the same diagram: after twenty years they are hardened, and often false air enters from there
• Piaggio 487840 air filter housing – the same thing for the Super Hexagon GTX 12": if yours is that, this is what you need

Who it's perfect for

This is the spare part for those who keep a Hexagon on the road and found their airbox cracked: this happens when the fastening gives way, when someone has forced it to clean the filter, or simply because twenty-year-old plastic hardens and breaks at the edge. The typical symptom is not noise: it's the scooter pulling poorly at low speeds, running lean, and not holding idle, because false air enters through the crack that the carburetor hasn't accounted for. Those who have gotten this far have usually already tried to seal it with tape or silicone and know it won't hold, and have already discovered that universal airboxes don't fit the Hexagon. On a vehicle of this age, an intact original airbox is one of the hardest parts to find: when it's available, you take it.

Frequently Asked Questions

Are air filters included?
No. This is the body of the box (position 1 of the Air cleaner diagram). The filter elements are codes 434363 and 434364, separate items. Take the opportunity to change them together, as you still need to open the intake to install the housing.

How do I know if the airbox needs to be replaced?
Typical symptoms are unstable idle, weak acceleration at low speeds, and lean carburetion that cannot be fixed with the air screw: these are the effects of false air entering through a crack. Check the housing against the light at the edge and around the fastening points, where it typically breaks first.

What is the difference with the 487840 housing?
They are two different airboxes for two different series: the 432542 is for the Hexagon 125/150/LX/LXT, the 487840 is for the Super Hexagon GTX 12". They are not interchangeable: if you are unsure, look at the code stamped on the installed housing.

Are gaskets and screws also needed?
They are not included. On the same diagram, you will find gaskets 433018 and 435328 and the screws (259166, 018640, 006125, 012533, 013880). After twenty years, gaskets almost always need to be replaced: reassembling the new housing with hardened gaskets means leaving the same problem unresolved.

Can I install it myself?
You need to disassemble part of the rear bodywork to access the intake, detach the hose, and redo the fastenings. With tools and experience, it's feasible, otherwise it's a job for a workshop.

Is it original Piaggio or a compatible one?
It is the original Piaggio spare part, code 432542. For these scooters, universal airboxes and aftermarket sport filter kits from third-party brands are available: these are different products that change the intake and require readjusting the carburetion.