The German supercar of hubs.
Back in the '70s, a certain German auto manufacturer claimed to be able to build a sports car that would perform up to its standards and need no service whatsoever, except for gasoline and the occasional set of tires, for up to 1,000,000 miles. Why didn't they? Two reasons: The first was cost and the second was that they'd be out of business in 10 years, because no one would need to buy another one of its cars again. The logic would apply to Chris King hubs, like the ISO XD 12x150mm Rear Hub, except that it doesn’t — not because the hubs don't last forever, but because the sport of mountain biking keeps growing, and new people learn of the supremacy of Chris King parts every day.
The technical superiority of Chris King's hubs — especially the rear hubs — is evident across all four dimensions of reality. In the first three, we start by observing the outside. In any color, King hubs look fantastic, with beautiful machining and finishing. The company's quality and consistency control are so stringent that entire batches of hub shells have been sent back to be melted down again if their anodizing is off by even one shade of hue. All King hubs' bearings are made in house and far exceed the precision and quality standards of competitors, on top of living within a legendary "all conditions" sealing system that is the same for its road hubs all the way up to its burliest mountain hubs — it's just that good — which leads us to that fourth dimension: time. King hubs last, and last, and last, and last.
But there's more to the inside story here. King's RingDrive freehub body engagement system is half of what makes the company's rear hubs so fantastic. The freehub uses a 24-pawl system to engage 72 (yes, a seven then a two) teeth within the hub, meaning that engagement is absolutely instantaneous when you put power to the pedals — no more of that floaty feeling that leads to a slamming of the pedals when you go to put the power down after coasting or when traversing tricky terrain. It means far greater control and response for single-speeding or trials-type riding, as well, not to mention that hallmark "angry bees" sound when coasting. And fear not for the frailty of what you probably calculate are tiny pawls and teeth, with all those numbers jammed into that freehub body, because King rear hubs can handle up to 800 ft/lbs of torque. Figure that world-class track sprinters are capable of putting out up to around 150 ft/lbs of torque at their peaks for only a few seconds. And yes, the axles, flanges, and every other part of the hub is at least that strong, making them more than tough enough for the gnarliest trails and biggest hits you can muster.
The Chris King ISO XD 12x150mm Rear Hub comes with a freehub body specific to SRAM XD drivetrains (XX1, X01, and X1) only. It has an ISO (6-bolt) pattern for disc brake rotors and can only be installed on bikes that use a 12x150mm rear thru-axle. It comes in three colors: Black, Silver, and Red.