Topeak Bike Rack Light Adapter

thingiverse

Topeak brand bike racks boast a convenient bracket at the back end where you can secure a light, however, not all lights are compatible. My tail light, for instance, features a universal design that's intended to be wrapped around the seat post with a rubber clamp. To give my light something to grasp onto, I created an adapter that matches the diameter of most common seat posts. Using 1/2-inch long 10-24 bolts, I attached it securely, and M5 bolts would also work well in this situation. While you don't necessarily need these bolts for stability, a wraparound light will still hold the adapter in place. Nevertheless, if you remove the light, the adapter will likely fall off, so take a few minutes to bolt it on properly.