I have this valve and i have also mounted it upwards like in the picture.
I don't think water or dirt can get in easily. The valve sits under the tank and when you are cleaning the bike the valve is in the closed position so nothing can get in.
However i am planning on refitting it again facing downwards. Not because of the dirt/water but more because i hope the sound will be a bit less loud. I mean this valve is a must have for the H2 but it is ridiculously loud!
If you do decide to get the valve make sure you hook it up to the trottlebodies vacuum and not to the valve thingy.
I don't think water or dirt can get in easily. The valve sits under the tank and when you are cleaning the bike the valve is in the closed position so nothing can get in.
However i am planning on refitting it again facing downwards. Not because of the dirt/water but more because i hope the sound will be a bit less loud. I mean this valve is a must have for the H2 but it is ridiculously loud!
If you do decide to get the valve make sure you hook it up to the trottlebodies vacuum and not to the valve thingy.