How do you attach a lawn mower engine to a go kart i onlky have a lawn mower motor not a small dirt?

You can't put a vertical on a go kart, not without expensive right angle gear box's.

You need a horizontal engine. No you can use a Vertical engine with a pulley take the spindle off the motor and replace a pulley there it will not be that difficult make them turn if i could send you a diagram but I don't know how to but you would have to size pulley on each axle a big and a small ill try to send a diagram the people that telll you otherwise are stupid.

Acually go to YouTube and research that, theres a video there that will compltely answer your question. =)