I was twelve years old and in Grade 7 when the mini-bike craze hit. There were two models to choose from: Bonanza or Keystone. Both were red. The Bonanza had a 2.5hp Briggs and Stratton engine, and sold for $150, while the Keystone had a little 2-stroke engine, and was slightly more sophisticated; it went for $175. Both did 30mph.
I didn't have $150, not even close... so I decided to make my own mini-bike. I heard about a frame for sale, and got a bit excited. When I saw it, the construction was crude, and it was quite unsuitable, so I decided to make my own. I drew a full size sketch on cardboard, and started assembling components. The engine was a 2.5hp Clinton, and the front wheel was off a wheelbarrow. The tubing was pipe, but it was free. My father borrowed a pipe bender from work, and we bent the tubes in the back yard on the lawn. I had no workshop then.
I could buy stuff from a guy who sold mini-bike parts out of his basement in the evenings. There was often a lineup to his counter. A centrifical clutch was $30, so I decided on direct drive with a jackshaft. Single speed, of course. For stopping, a foot operated "spoon brake" pressed against the rear tire; they weren't great. The front number plate was created from thin plywood, and "6x" painted on. I saw it in a motorcycle magazine, and it was cool.
The frame had front suspension. A single spring underneath the head tube (on an extended steerer that didn't run in any kind of bushings or bearings) was designed to ease the shocks. However, because I didn't know what I was doing, the suspension wasn't really suspension at all... In the photo the spring is replaced with a spacer. My learning curve was steep. I hadn't figured out how to stick the tubes together yet, so my welding inspector Father was good enough to coerce a friendly welder to zap the frame for me in exchange for lunch. It took several hours even though it's a simple design.
I think it took about 4 months and cost about $110. I painted it metallic blue, and the seat was red. The photo below is my 13th birthday riding the bike at Jericho Beach, for those of you who know Vancouver. I remember once I rode it a few blocks to the local gas station. I had to sneak down alleys—no licence, no insurance. I told the guy to "fill it up!" and he did. It took 4 cents, so I gave him a nickel and told him to keep the change. Things were different then, right?
Next year I decided to sell it. I put an ad in the local paper for $85. It was summer and I was picking strawberries for $5 a day. When I got home, the bike was gone. My mother told me a young boy had looked at it, liked it, and asked if he could make an offer. She was quite unsure as to what his offer would be... when she asked, he said "eighty-four dollars?" Sold!