Piaggio 840439 Transmission Cover Cap – Beverly, MP3, X9, Nexus 400/500

The Piaggio 840439 is the transmission cover small lid, the plug that closes the inspection opening on the transmission casing. It is the original spare part intended for almost all Piaggio Group 400 and 500 cc maxiscooters: Beverly, BV, MP3, X8, X9, X10, X Evo, Gilera Nexus and Fuoco, Aprilia Atlantic and Scarabeo. Product code 840439.

✓ Strengths

• Original Piaggio spare part – official catalog designation "transmission cover small lid", code 840439
• Keeps out water and dirt – closes the casing inspection hole and protects the belt, rollers, and clutch from the entry of dust, mud, and water
• One code for the entire 400-500 family – Piaggio, Gilera, and Aprilia with the Master 400/500 engine
• Replaces in an instant – no casing disassembly required, it is reinstalled by hand
• Very low cost, prevents expensive damage – operating with the inspection hole open means water on the belt and premature wear

Technical features

Vehicle compatibility

Vehicle list from the official Piaggio B2B catalog.

Who it is perfect for

This is the part you need when, after a transmission service, you notice that the inspection plug is missing or has cracked: this often happens because it is made of plastic and easily comes off when the casing is disassembled. It costs very little and prevents water and dirt from getting onto the belt. It is also the right item for anyone restoring a Beverly, MP3, or Nexus from a few years ago and wants everything to close up like the original.

Frequently Asked Questions

What part is exactly the 840439?
The 840439 is the transmission cover small lid: the plug that closes the inspection opening on the transmission casing. It serves to prevent water, dust, and mud from entering the compartment where the belt, rollers, and centrifugal clutch operate. This is the official Piaggio parts catalog designation.

Is it suitable for both the Beverly and the MP3?
Yes. The 840439 is common to the entire Piaggio Group 400 and 500 cc maxiscooter family: Beverly and BV 400/500, MP3 400 and 500 in all LT, RL, Sport, Business, and MAXI versions, X8 400, X9 500, X Evo 400, X10 500, Gilera Nexus and Fuoco 500, and Aprilia Atlantic and Scarabeo 400-500.

I found the same part with code 833319 or 841475: is it the same?
Yes, 833319, 841475, and AP8560224 are cross-references for the same item that appear in spare parts catalogs depending on the model and year. If your parts manual lists one of those codes, 840439 is the correct part.

Do I need to remove the casing to change it?
No. The small lid closes an external inspection opening: it is replaced from the outside, without opening the transmission casing or touching the belt and rollers. It is one of the fastest spare parts to replace on these scooters.