I'm really liking this thread Maxvision, here's a link to purchasing a mini-chopper all the steel tubing is included, you just have to figure out where weld in a bottom bracket for your pedal crank to build it as a motorized bicycle.
Here's the Link below just click on it to go to the page:
Mini Chopper Frame Building Kits
QTY- 1 Mini Chopper You Weld Frame & Fork Kit.
Parts included (Frame Kit)
2- Lower Frame Rails
2- Upper Aft Ends
1- Rear Hoop Section
1- 12"x9" Motor Mount Skid Plate
1- 6" Length Neck Tube W/ Bearings
1- Backbone Support
1- Seat Post
2- Rear Axle Flange Brackets(Live or Dead axle avail.)
2- 38" Fork Tubes
1- Drag Bars
2 -Triple Trees
2- Fork Tabs
You can do it all you need is welder.
Peace Crazy Horse.