Yeti's new SB100 fits into a growing category of category-less bikes. This can be difficult to comprehend; we humans like to put things in boxes. A 100-millimeter-travel, carbon-fiber 29er from a race-bred brand like Yeti? That's cross country, of course. Except it's not. A dropper post, beefy fork, meaty tires, aggressive geometry, wide bars and a total weight over 25 pounds. That's a trail bike. Except it doesn't have enough travel to be a trail bike, right? And aren't all mountain bikes essentially trail bikes?

Luckily, you don't need to spend much time mentally categorizing the SB100 because it unequivocally checks the most important box of them all: damn fun. For a bike that's short on travel, it doesn't feel limited, and while it won't descend with the same reckless abandon as a plush, long-travel 29er, it's playful, an ultra-efficient climber and likes going down as much as going up. In a nutshell: take the SB100 to Canada, but enter the BC Bike Race not the Whistler EWS. 

 

The SB100's ride qualities can be attributed to the kinematic changes Yeti made in configuring its Switch Infinity linkage for a shorter-travel bike. Also attributed to the revised Switch Infinity? The bottle-cage bosses in the front triangle. Normally, it would be out of place to mention such a small detail so early in a review, but this is a big deal.

Yeti's existing Switch Infinity mechanism limits space in the front triangle, banishing water bottles to the dreaded downtube underside, but when engineers set out to transition its ASR XC bike into its SB line some two years ago, they saw an opportunity to solve the bottle-cage design challenge since the bike has only 100 millimeters of travel. Engineers tested five iterations of a modified Switch Infinity, and ended up rotating it 90 degrees, slimming it down, tucking it behind the seat tube and integrating it into the frame, resulting in a lighter, more efficient package. The way Switch Infinity works doesn't change—it's still based on a translating pivot point and still uses the same links.

The new placement cuts weight (the SB100-specific version is 60 grams lighter than the Switch Infinity on Yeti's longer-travel offerings), allows for an uninterrupted seat tube to accommodate whatever length dropper post your inseam dictates and makes way for kinematic changes. On the SB100 version, the slope of the linear leverage ratio curve is slightly steeper, allowing the suspension to be tuned specifically to create a more efficient climber, without sacrificing any support as the shock gets deeper into its travel.

Yeti recommends setting sag at 32 percent, or 12 millimeters of shock stroke, although I ultimately had to take about 15 PSI out of the shock to get the full travel out of it. Once I had it dialed, though, the shock felt active and its travel is usable; 100 millimeters truly feels like 100 millimeters—the shock doesn't blow through its travel mid-stroke. I also spent some time on the Beti version of the SB100, which along with a few female-friendly touchpoints, also comes stock with a lighter shock tune. I always wondered if that particular selling point on 'women's-specific' bikes is merely marketing speak, but in this case setting sag at 32 percent on the Beti felt exactly right on my first ride, so it required slightly less tinkering for someone of my body weight (135 pounds).

As with all the Yeti 'SB' models I've tested, the SB100 hauls up climbs quickly and efficiently with the shock open and the Open Mode Adjust in the middle setting. 'Climbing' in southern California generally constitutes brief fire-road gut punches devoid of traction and flow, ideal for ground-gobbling 29ers. It was on these soul-stealing climbs when the benefits of the steepened, 74.2-degree seat tube angle came into play, with the front wheel staying planted on the ground as I ground up toward the sky. That said, the bike doesn't give you license to sit back and expect the geometry to do the work for you—at the apex of a few of the steepest climbs, weight was certainly required over the front wheel to keep it tamed.

If the $900 carbon-wheel upgrade is in the budget, it's a splurge worthy of the quick acceleration with which you'll be rewarded. And for the weight weenies who weren't turned off by the opening paragraph of this review, the difference in weight is minimal, with the Yeti spinning on stock DT Swiss XM 1501 wheels coming in at 26.15 pounds (with pedals) and the Beti with the DT Swiss XRC 1200 upgrade registering at 26.07 pounds. Light, but certainly not the featherweight status of a true XC bike. Then again, descending on the SB100 doesn't feel like a true XC bike either, which is exactly what Yeti intended when it outfitted the frame with a party kit, including the new 120-millimeter Fox 34 Step-Cast fork, Fox Transfer dropper post, Maxxis 2.3 tires—Minion DHF front and Aggressor rear—760-millimeter bars combined with a 50-mil stem and a 180-millimeter front brake rotor. Though if I were picking a spec package, I would opt for the non-race version of the X01 build or the GX Comp, which both add some weight, but come with dependable Shimano XT two-piston brakes and Shimano rotors. Full disclosure: I also don't race and ride quality always ranks higher than weight on my priority list.

Regardless, the SB100's combination of very capable parts, along with its forward-thinking geometry is what gives the SB100 its value, not its weight. After warming up on a couple of steep, traction-less, but not particularly technical chutes, I tentatively pointed the SB100 down more technical trails that would have terrified me on other bikes of similar travel, and was relieved by the ease of control, no doubt due to its confident front end and aggressive geometry. Its 67.8-degree headtube, 332-millimeter bottom bracket height and Yeti's standard 437-millimeter chainstays are similar to Yeti's existing 4.5C 29er (which is staying in the line for now), though the SB100 has a longer reach and thus a 44-millimeter-offset fork for the added ease of weighting the front of the bike and gaining more front-end traction.

Of course, the only downside of buying a Yeti is you have to be able to afford a Yeti, and given a complete SB100 starts at $6,000, this might not always be possible. There are other bikes in this not-so-xc category—the Santa Cruz Tallboy/Juliana Joplin have similar ride qualities and can be obtained for significantly less money—but the SB100 sets the bar for how a bike in this non-category should ride.