When I open my flip up gas tank refuel cap there seems to be a large build of pressure. At the opening there is a brief 'whosh' sound. I don't recall having this kind of pressure release on my old Stratos 189V from 10 yrs ago. Is this normal?
The old Nitro user guide safety video (2012) at the 1:05 mark states the internal gas tank is always vented.
What is the normal condition?
Thanks