Thread: Electrathon - A Different Kind of "Hotrod"

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OK, this is supposed to be a build thread, so lets get to it. If I seem wordy it's because I want to explain everything as best I can to those who have never been exposed to this type of thing before...

First thing is to decide which type of car to build. Of course, we could build a conventional 4-wheel car, but since friction is a consideration, eliminating the rolling friction of one tire on the ground seems to be the way to go. The simple fact that probably more than 99% of all Electrathon cars are 3-wheeled lends credence to that practice. So.., with that in mind the next consideration is whether to make our 3-wheeler a cycle-car or a tricycle.

Folks who have ridden old Harley Servicar 3-wheelers know that those things will dive right over the front wheel and flip over at relatively low speed. The problem is that the high center of gravity (CG) transfers forward and outside the triangle formed by the three contact patches of the wheels. In order to stabilize a tricycle in a corner, it is necessary to get the CG down low and between the rear wheels so it won't dive over the front wheel. To do that we need to stretch the wheelbase and move everything down and rearward. The winningest team in Electrathon, Cloud Electric, successfully uses the tricycle configuration, but up in the Northwest they run mosly on long courses or ovals.

On the tight parking lot "road courses" we run most of the time here in Florida, quick handling is important. With a cycle-car configuration we can keep a shorter wheelbase for quick steering response, move the CG around pretty much at will to put components where we want them, and still not worry about the car having a tendency to roll over. I have video of one of the Kennedy High School cars from Iowa actually smoking the rear tire in a tight turn and all 3 wheels stay firmly on the ground. So, it is a cycle-car style that we will build here.

I have an advantage in that I have done this before. The car below (also pictured in my initial post) was originally conceived by my students, the design refined by me and a former teaching assistant, and built by my students and me. That was in 2004. Since then, this car has proven itself to be reliable, consistent, and driver-friendly. The new car I am building here is similar to this, but with a few refinements I have learned along the way.