Whether you prefer threaded bottom brackets for their silence, their ease of replacement, or-like us-for the pure romance of these precisely machined beauties, we can all be grateful that craftsmen like Chris King agree. If you're the lucky owner of a dirt-loving frame with a 73mm threaded BB shell, replace your worn-out bottom bracket with the Chris King ThreadFit 30mm Bottom Bracket. As the latest addition to Chris King's ThreadFit line, this cylindrical powerhouse keeps 30mm spindle cranks turning silently with its made-in-house bearings while you mash the pedals over rocky cruxes and rutted descents. King even makes the system kind to the novice at-home mechanic with an integrated grease injection system allowing you to give a little love to your bearings without a trip to the shop.