Inconspicuous way to improve performance without having to invest in a completely new exhaust system. Most Piaggio models have exhausts that are divided into two and the manifold has a resonance tube which reduces the engine’s power. Changing this manifold for a version without this tube will release more power. A positive side effect is that it resembles the original.IMPORTANT NOTICE !!!For some models, there are two different versions of the manifold. A short and a longer version. Please first measure the distance from the manifold flange (connection to the muffler) as shown on picture 2. This can also be easily measured directly on the vehicle. This article is the long version with a size of about 8-9cm.