Road bikes are meant to be light and fast, which is why they don't make bike baskets for them. This project started as a practical effort to create a modular attachment system for carrying cargo to and from the PRL. A simple design with interchangeable parts for different uses.
A rear-light powered by propane slowly took over the goal.
Design Philosophy
I wanted something reliable and robust—a frame that works flawlessly in the background without me thinking about it. Safety was paramount: there's a quick-release mechanism if things go south and a safe ignition system for the flame.
The core hardware came from a camping burner with a hose attachment to a propane tank. I modified the casing into a sleeker shell that slides onto the back of the bike.
Engineering the Frame
The hardest part was creating a lightweight yet sturdy aluminum frame. The design evolved significantly—my initial idea was a detachable single horizontal bar connecting to the seat post, but it proved unstable. Most bike racks use two additional support beams near the rear wheel axle for stability. While not my original vision, I decided to permanently attach the frame and make only the attachments modular.
The frame is made from 2mm sheet aluminum bent into roughly hexagonal cross-sections—a geometry that could be manufactured on a press brake. 3D-printed attachments lined with rubber from an old tire grip firmly onto the frame. Figuring out the organic geometry of the bike required magnetic angle gauges and rapid prototyping.
The 3D printed components feature G2 blends, which Shapr3D handles beautifully. G2 blends create smoother transitions than simple fillets. Apple takes this even further with G3 blends on their device corners—the ultimate in tactile refinement.
A render of the flame holder in Shapr3D's visualization feature.
Finally, it was all powder coated black at the recommendation of Bear, the best CA at the PRL.
Beyond looking cool, the flamethrower doubles as a heat source on cold nights and makes excellent marshmallows.
The original bike basket attachment is still in the works, along with a cast bronze jet engine that blows soap bubbles. I'll make it!