Every time it rains while riding a bike or the car has been soaked in rain all day, I often feel the transmission slipping. Although the feeling is very slight and short-lived, it is always weird. I checked and it should be the cooling air guide of the transmission box. It was caused by the pipe, and I happened to have spare parts on hand. Today we will talk about the impact of this pipe and see the filtration effect of the Caigua cloth filter that was replaced last time!