you need to fix your caliper.
sounds like your caliper piston(s?) are leaking.
maybe you're lucky and it's just the brake line, but since you said "from under the brake pads" it's more than likely the pistons.
Some calipers can be fixed, some can't (lack of replacement parts)
We can't tell since we would need pics of the kart and of course the caliper in order to identify it.
Since there is no such thing as a suzuki rm80 go kart!
(someone mounted a dirtbike engine to a kart but that doesn't tell us anything about the kart much less it's brake calipers)
'sid