As part of the effort to help PeterB’s Battle Mountain run, we’ve been working one some front wheel fairings. These are added to the bottom of the factory pants to shield the exposed lower wheel. This has been a real challenge. The shape has to enclose the front wheels yet being wide enough to allow the wheels to travel through the steering arc. Also coming up with a shape that allows mounting to the curving bottom of the pants has been tricky. At this point, I’ve gone through three iterations of shapes. Each iteration involves building a plug, mold and part. So far, each shape has been symmetrical side to side so that I can use a single mold and trim the resulting parts to fit right or left. Before showing the evolution of shapes, here’s a photo of the latest iteration, painted and mounted on my DFXL.
The first shape that I came up with is a long teardrop shape with curved sides. The problem with this shape was that in order to open the tire slots wide enough to allow the maximum steering angle, the slots opened into the vertical part of the sides (due to the curve of the sides).
This lead to a second shape with vertical sides. This allowed plenty of room for cutting the tire slots in the bottom without the slots going up the sides. But the fairings looked massive when attached to the pants.
The third shape was based on the second but was shorter and with reduced volume.
So this is where we are right now. This 3rd iteration is smaller and there is enough room to cut the tire slots. It’s mounted with the use of magnets and tape as shown below.
However, I’m still not happy with the shape. The front seems too blunt and the tail should be elongated to make it more teardrop shaped. If I can muster the energy, I think that I’m going to modify the first shape to overcome its flaws. In the photo below, you can see the current shape in red and the first shape in white.
Oh and by the way… We have not tested the idea of adding fairings to the pants. For all we know, these things could add more drag than they’re worth. We’ll do some roll-down tests to make that determination.