well ive topped it up using dot 4. i havnt toped it up too high but when u lean the bike it obviously swooshes about because it is a thin liquid. i think my brake pads are ok tho. my friedns noticed this withn his bike when he changed his caps over too
the ONLY way the FLUID can go DOWN is if there is a LEAK or the PADS are worn. now when you put new pads in, fluid will go everywhere.