I am looking to put a weedwacker engine on to a bike as a fun summer project. My idea is to
Take the engine and weld it to an trick bike peg the that to a gear and chain the connecting it to the back wheel.

Do you think ths would work?

Please help

Sure it will work, check out kingsmotorbikes.com

Also you could check out hobbytalk.com, some guy there built one and posted pictures.