YouTube will make you look like a pro in no time
This guy has some good videos for your motor, Note the tiny screw that is missing from the black nut
How To Troubleshoot and Repair 2 Stroke Motorized Clutch 66/80cc
Click on the videos that look like your motor, He has videos on the other parts click on the ones that interest you most like maybe the one about the chain next.
Hughes Motorized is all bout cool, custom-crafted motorized toys. Stay tuned for some cool toys !
www.youtube.com