Every garage has one: a dusty bicycle frame, a rusted scooter missing its fairings, or a pile of orphaned motorcycle parts that "might be useful someday." For the average person, these are junk. For the curious tinkerer, they are questions. But for the Evil Genius—the one who sees a 49cc engine where a pedal crank should be, or a stretched chopper frame lurking inside a child’s minibike—these are answers waiting to be built.
If you have ever searched for a guide that bridges the gap between whimsical theory and welded reality, you have likely stumbled upon the cult classic: Bike, Scooter, and Chopper Projects for the Evil Genius.pdf.
This article is your complete roadmap to understanding, locating, and executing the mad science contained within that infamous PDF. Whether you want to build a gasoline-powered skateboard, a folding electric scooter, or a springer front end for a stretch cruiser, this guide will show you why this digital file has become a bible for backyard fabricators worldwide.
The premise of the book is simple: you do not need a professional fabrication shop to build something cool. You need a welding rig, some basic tools, a supply of scrap metal, and a healthy disregard for convention. Bike- Scooter- and Chopper Projects for the Evil Genius.pdf
Graham and McGowan structure the book to take the reader from a novice tinkerer to a confident fabricator. The "Evil Genius" moniker is applied playfully; it suggests a level of ingenuity that goes beyond the ordinary, encouraging builders to modify, hack, and improve upon standard designs.
A three-wheeled beast where the rear wheels are wrapped in PVC pipe for drifting. The PDF includes a parts list sourced entirely from Home Depot and a dead treadmill motor.
High-level steps (example: electric conversion): Every garage has one: a dusty bicycle frame,
Quick sizing rules:
Let’s assume you have the file open on your laptop in the garage. Now what?
Step 1: Print the "Cut List" The PDF contains a unique feature: a printable template section. Do not scroll past Page 142. Print the 1:1 scale paper templates for the chopper triple trees (the parts that hold the front forks). Tape them to the floor. Quick sizing rules:
Step 2: Ignore the Electronics (Initially) Because Brad Graham is an electrical engineer, the first third of the book obsesses over Ohm's law and soldering. If you are building a chopper, skip to the fabrication chapters first. Come back to the scooter motor controllers later.
Step 3: Modify for Material Availability The book was written when steel was cheap. If the project calls for "1-inch DOM tubing" and you have only "EMT conduit," the PDF includes a "Danger Zone" sidebar explaining when materials are interchangeable and when they will kill you.
The book includes a dedicated section on the tools required for the "Evil Genius" workshop.