Cool Cool Bye

Both are about people with limited technology that somehow have mechs and use them to dig and fight others. Both have a little mole mascot, and like to use exaggerated expressions to add some silliness to it all. Cool Cool Bye feels like what Gurren Lagann would have been like if it had been made in the 80s. 

No time for plot (as it was common in that era) - there is one non-stop race-and-battle for ya. Funky transport, big robots, speaking blobs, cute girl, some magic in sci-fi-ish post-apocalyptic world - all check. Cool Cool Bye has seemingly more detailed drawing but lame animation. Interesting hover bikes design and good ending song are only worthy parts for me. Birth is much better overall. Story has some depth actually, if you can find it behind nonsensical dialogues. And animation is just awesome.