Beginning with the final pressing of the venerable SB 66 a couple of years ago, Yeti has found itself in an unending refusal to settle for its current collection of BOTY accolades while playing to the fickle affections of the industry. The SB66 has the be all, end all of mountain bikes, and when Yeti scrapped it, we were in a state of enduro mourning right up until we threw a leg over the SB6. At that point, memories of the SB 66 faded into the all mountain ether, and we were convinced we'd reached the terminal product of six inch innovation. For 2016, though, the SB6 Carbon GX Complete Mountain Bike is back with another tweak: a 148mm Boost rear axle. This means that the rear end is even stiffer, so the bike's preternatural ability to descend like a DH rig but navigate backcountry treks like a trail bike becomes even more pronounced the new SB6 is an even super er super bike. Despite the new axle standard, several key elements of Yeti's flagship bike return unchanged from the previous year. Not surprisingly, the Switch Infinity suspension system is one of them. The SB6's Switch Infinity originally replaced the Switch Link design, which experienced a momentary harshness when rapidly successive hits kept it hovering above the 30% stroke point. Switch Infinity replaces the Link's sinuous travel arc with a linear plane of motion, so the eccentric link changes direction without getting caught in the minute dead spot that produces that harshness. Of course, 95% of all riders won't ever push the Switch Link hard enough to experience this dead spot, but Yeti being Yeti went ahead and fixed it anyway. For those of us who are our own mechanics, Yeti also simplified maintaining the Switch Infinity by including easily accessible grease ports, which do away with the need for time consuming rebuilds. Other than those two changes, the suspension systems are fairly similar. Like the Switch Link, the Switch Infinity slider travels upward under the first phase of compressi...