So, you bought a new road frame, but your existing crankset is a BB24 and the frame is a BB30 — the frustration is stacking. However, your question of why nothing is consistent anymore has been answered by Rotor. Yes, Rotor designed the BB30-BB24 Converter Road Bottom Bracket to make changing components between frames a breeze.

Rotor created a smooth, after-market converter using its labyrinth seals. Labyrinth seals have a series of grooves, or teeth, where the male and female pieces slip together — often perpendicular to the threads. These grooves create a maze that fluid would need to pass through in order to create a leak. Additionally, the labyrinth seals provide unparalleled protection from elements such as dust, water, and mud.

Most importantly, though, this converter allows you to run a conventional BB24 crankset with a BB30 frame. And even better, at around 108 grams, it allows this without stacking up needless weight.

The Rotor BB30-BB24 Converter Road Bottom Bracket is compatible with conventional BB24 cranks from Rotor, Shimano and Shimano-compatible brands. It features steel bearings, and it's available in the color Black.