My grandkids have this ATV. It's plastic, and runs on a 12v 8AH battery
that won't charge any more. I haven't priced them, but they're probably
proprietary and spendy. Would a common lawnmower/motorcycle battery from
Checker work? They're close to the same size. Or would it have too much
amperage and burn up the motor?

Steve

--
"...the man who really counts in the world is the doer, not the mere
critic-the man who actually does the work, even if roughly and imperfectly,
not the man who only talks or writes about how it ought to be done."
Theodore Roosevelt 1891