End of series Yamcha VS Shounen series with a twist

[The Drunkard Kid]

IIRC Goku doesn't even learn to sense ki until he trains with Kami

Nah, Goku was able to sense Piccolo Daimaou all the way from Korin's Tower after he drank the Super Ultimate Water (I think that's what it was called). Near the start of the series, he was also able to sense a pirate robot, but that might have just been with other senses since there's no indication that it had ki.

Training under kami was when he learned how to use his regular and ki-senses as a form of radar sense, though.