Aerodynamic end cap for square Thule bars

thingiverse

Here's an attempt to increase the range of my electric car with Thule Bars installed. The chosen profile and turbulator is inspired from a Hang glider control bar section, which I believe will make a noticeable impact on efficiency. To fit them flush with the feet, the base is angled perfectly. The solution to this problem lies in 3D printing these bars. Replacing them with aeroblade alternatives is cost prohibitive, but printing them is a feasible option. The provided file is for the left side; don't forget to mirror it before printing the right side. Installation is simple: remove the actual end cap and slide the printed one into place. A heat gun can be used to soften the cap, making it easier to insert and ensuring it stays in position. I also experimented with 3D-printing middle sections, but I found that it consumed too much plastic. However, I have noticed a decrease in noise since installing these bars, although I'm still waiting to confirm whether my Kilowatt per kilometer reading has decreased as well. Last summer, I calculated a 7% drop in range just by adding the bars on the roof. To print them, I used an ANET A8 with PETG and a 0.8mm nozzle at 240 degrees Celsius. They seem sturdy enough to withstand transportation, having already survived a Christmas tree delivery without issue.