Classic Mini-bike Build
Over the last few decades, vintage mini-bikes have become increasingly sought-after by both collectors and enthusiasts. Manufacturers of old mini-bikes include Rupp, Cat, Bonanza, Lil Indian, Ruttman, and Fox. This little gem is a Western Flyer model SS-300, which featured a spring front suspension.
Several years ago, I bought this mini-bike not running. It had a frozen clutch, rusted chain, and no brake. All of these were simple and cheap to repair.
Western Flyer Mini-Bike
This bike is indeed mini. Only 48" long and 32" to the top of the handlebars. Although Western Flyer mini-bikes were originally powered by Tecumseh engines, this one had a Briggs & Stratton 3.5 hp engine when I bought it. The spring front suspension sits below the front steering tube. It doesn't really do much, but it looks good!
Small Engine Repair
If you've ever worked on a car or motorcycle engine, it's an absolute joy to work on a small gas engine. The majority of old mini-bikes and go-karts were originally fitted with either Briggs or Tecumseh four-cycle engines. These old flathead motors are durable, reliable and easy to repair. If you don't have a motorcycle work stand you can prop up the bike on a thick block of wood.
3.5HP Briggs & Stratton Engine
In 1953, Briggs & Stratton revolutionized the Lawn and Garden Industry by developing the first lightweight aluminum engine. Lighter and less expensive than their cast iron counterparts, these engines made lawn and garden equipment accessible to the masses of post-WW2 Americans moving to the nation's new suburbs.
Effects Of Ethanol Gas
Ethanol is used in today's gasoline as an additive, and E10 gasoline today contains roughly 10% ethanol. Ethanol has a shorter shelf life and a shorter tank life than gasoline, and can begin to break down in as little as three weeks. Another problem with ethanol is that it attracts water and "breaks down" faster than gasoline.
Ethanol is the same type of alcohol that is found in an alcoholic drink, which works somewhat like a cleaning agent. It also increases vapor pressure in gas, which may cause vapor lock in the carburetor. These issues are not so bad with daily transportation vehicles, but with small engines they are problematic.
Make sure to store your gasoline properly and try to use it in a timely fashion. Use a product like Sta-bil and add it as directed to the gas. This will help prolong the life of the gas and keep it from harming your small engine.
It's All About The Smiles
Classic mini-bikes can go up to 25 miles an hour, so be careful when you ride one. When riding, be a good influence to the younger kids. Wear a helmet and obey traffic signs.