Legacy

Originally there was a challenge set forth by James M. to convince a team of hobbyists to compete in a build-off challenege called 'The Gauntlet' which was our first exposure to Cycle Kart building. We didn't know much about Gittreville or Stevenson back then, but were very curious.

At that time it seemed the best thing to do was to borrow designs from golf cart surplus stores and motorcycle junkyards. Maybe because the Motor City (Detroit Metro) is really a place where people built REAL cars (and real race cars). The concept of building a go-kart usually means having a place 'Up North' to drive it around in the dirt.


This was the first 3D model I built for this purpose. It was based on the idea that the lowest possible center of gravity depended on getting the occupant below the frame rails. It also was based on the idea that the front end could be a cross-car leaf setup, with independent wish-bones similar to designs of late 30's indy cars and grands-prix cars.




At that time I was inspired by the W154 Mercedes Grands-Prix design that won the world championship in 1938. I thought it would be novel to create an aluminum body; my own version of a 'Monopoly Car'.




W-155  or The Rotten Tuna
So when we started building this design (and I say 'WE' because it was a team effort at that time) we knew absolutely nothing about fabrication or chassis design.

I say again, in 2013 when we started this nonsense we were not fabricators, or had any shop tools, it was just an idea. It started at Harbor Frieght, with the purchase of a Predator 212. The box sat in my garage for months while we came up with a plan for designing and building.

One of the most complex things to understand was how build tolerances can affect chassis dynamics. even the slightest variation from left-to-right causes dramatic effects at 35mph. But we didn't know any of that, we just wanted to weld and grind metal which was fun!


This last pic shows a cardboard mockup for the body, but it never materialized. I had a difficult time justifying the purchase of large blocks of foam for a fiberglass body. And I lacked the shop tools and space to do aluminum body panels the way I wanted to. Sure I could have made it work but I had a vision that there was a better more intuitive way to make automotive shapes affordably.


The above pic shows a few issues with this design. It requires very precise fixturing for both welding and alignment. The more welds happening in a small place, the more chance for dimensional deviation. This setup was soft and responsive with very little bump steer, but as we found out liked to break. Our welds at the kingpin failed making it a 3-wheeler at one point.

We learned alot building the first cyclekart, and ultimately knew that it had to be lighter. After an impromptu weigh-in session, (and a few highly precise ones) it was determined that it weighed 205lbs wet.


Then it was time to test! Our inaugural event was an ice event where we did mostly testing, and just for show we attached a few aluminum panels. Nothing aesthetic about it, just a way to keep the snow off our legs.
Rotten Tuna (left), Mantua Special (middle), Paul's Custom (right)

What we learned was that welding is tricky with a MIG and flux core. We learned that welds like to break when they dont penetrate well enough, or if there is contamination. It's also clear that studded tires (or chains in our case) put alot of strain on the bearings and steering.

basic chain-stock on drive tire only
When it comes to ice racing, it's key to paint any metal surface as it will get wet and rust. It's also a good idea to carry a 'fix it kit' at all times, because things break. Extra throttle cables, brake pads, fuel line etc. Boy scout the shit out of your adventures is the only advice I can offer! -CW

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