Before someone asks: Yes, I have used the Sufu here, but not found anything ugly, what could fit – apart from ‘times fast’ gear oil change … Live in a nice settlement on/on’m mountain and recently I went down here with a window. By a wall, it struck me quite clearly, when I gave light gas: Baaah, what is that for a grinding noise ? Sounds gruesome / harmful ! Trit only when giving gas, so at load on – in the 1st m.E. relatively (very ?) loud, in the 2nd still clearly noticeable, in the 3rd is then already the rest drumherum louder. With window / slide roof too (and radio out) one listens to it in the car inside nix ! To say that this noise at increasing speed in the respective gear is still quieter than louder. Also it somehow does not play a real role, whether I ride up with a lot or little gas or only when rolling down the hill is not easy to get the pin all over again?