Father’s Day is coming which has us thinking about our dads and the projects we did together that got us into all things mechanical back when we were kids. If you have been looking for a way to spend time with the kids and teach them valuable skills while having fun, there is nothing better than tackling a kid-sized motor vehicle with them, whether mini bike, go-kart, or pit bike.
The simplest is the traditional mini bike, typically just a bent tube frame, a rub block for a brake, and no suspension. Go-karts are the next rung up the ladder, and in their purest form are just four wheeled mini bikes, rub brakes and all, but can get much more complicated and faster. The most complex is the mini motorcycles commonly referred to as “pit bikes” because they are often used to get around the pits of a race track. Pit bikes typically have brakes and suspension on both wheels, plus a multi-speed transmission and a clutch of some sort.
The choice between mini bike, pit bike, or go-kart comes down to two things. First, how coordinated are your kids and how good are they on a regular bicycle? You don’t want to introduce them to power if they keep crashing a pedal bike. Second, how much room do you have in the garage or shed? A mini bike or pit bike takes up a lot less room when not in use, and is a lot easier to transport to a riding area.
Paring a motor down to its most essential parts and putting it in a kid-sized vehicle simplifies things, and the excitement of being able to pilot it makes kids eager to learn about it. The vintage air-cooled flathead Briggs & Stratton or Tecumseh engine that powers most of these things only has about a dozen moving parts, and no special tools are needed to take them apart. The more modern Honda or Predator OHV motors are a little more complicated, but still really easy to take apart and put back together. Most importantly, they are very easy to understand.
Take a look on your local Craigslist or Facebook Marketplace, and you are likely to find dozens of potential projects. You might be surprised at the prices some people want for certain bikes, like Rupp, Bonanza, or Taco brand, but that is merely the power of nostalgia. There were many other makers out there who’s bikes are not as dear to the hearts of overgrown middle-aged kids, and they are just as much fun to ride and wrench on. Amazingly enough, Old Mini Bike Warehouse has replacement parts for these old bikes, and even old style kits if you want to build your own.
If you want to take the easy route, the Monster Moto 80cc Classic mini bike like the one we were playing with behind the shop around Christmas can be had on Amazon for about $400 with shipping. You can start with a new running bike and then modify it and learn about how engines make power, and how to make more. The beauty of this path is you get a professionally welded frame with fat balloon tires, and even a modern disc brake for safety.
Clymer has been working on a mini bike for Project Bike Project: Minibike – a Bird Engineering Thunderbird from the 1970s with a Tecumseh 4 horsepower motor in it. This bike was picked up complete, but not running, for just a few hundred dollars at a swap meet. You can follow along on our YouTube channel as we evaluate it, strip it down, fix it up, get it running and finally customize it. Later we may even take it racing and try to make more power from that old, obsolete flathead, possibly with a smog pump supercharger.
You may think that Clymer doesn’t make a manual to help maintain mini bikes and go-karts, but you would be wrong. The Clymer small engine line includes the Tecumseh L-head Engine manual, and several different Small Air-Cooled Engine manuals which cover many brands, plus a Briggs & Stratton L-head Engine specific manual as well.