I have a brand new Svartpilen MY2019 and with the tank full I have a weird noise when moving the bike FW/BW, like when pumping the front fork. Sounds like a plastic object is banging in the tank. Maybe the sensor….?
Another issue that might be related or not, is that when the tank is full, the indicator on the dash misses 2 bars…
My 401 has that sloshing fuel noise when the tank is full too. I’m pretty sure that’s normal.
The fuel level sensor on these bikes is very poor. Mine used to be like yours, only read 6 bars when full. I made a post on this forum about a tool I made to insert into the tank and bend the fuel level float lever/rod slightly downward. This allowed the float to move upwards more inside the tank when full, so the gauge actually reads full (8 bars) now when I fill it to the plastic bar that sits in the filler opening.