The area around the carburetor butterfly and slide valve gets extremely dirty.
This carbon-like stuff comes from blowback from the engine and so on.
Even with fuel injection, the butterfly gets dirty and won’t close properly, which can cause running problems.
You can disassemble the carburetor, but you can also clean it from the side with a quick spray of carburetor cleaner.
(Don’t overdo it though.)
As the miles add up, the carburetor area gets pretty gross. ★
Pokidam
