

There was a brief moment in time where it seemed as if 29ers were at risk of fading away, relegated to XC race courses and mellower terrain as 27.5” wheels stepped into the limelight. Luckily, that moment quickly passed, and this past year we've seen a resurgence of mid- to long-travel 29ers, with more on the way. Yeti's entry into the fray is the SB5.5, a bike that's meant to be able to handle everything from the rigors of the Enduro World Series to casual after work rips on your local trails.



Equipped with Yeti's Switch Infinity suspension system, the SB5.5 has 140mm of rear travel matched with a 160mm fork up front. There are two different versions of the full carbon frame, the Turq and the Carbon. Both share the same geometry and stiffness, but the Turq uses a different carbon layup that results in a half-pound of weight savings, along with a higher cost.



Yeti SB5.5 Details



• Intended use: all-mountain / enduro

• Wheel size: 29"

• Rear wheel travel: 140mm

• 66.5° head angle

• Carbon fiber frame

• BB92 bottom bracket

• Sizes: M, L, XL

• Weight (as shown, size L w/o pedals): 28.5 lb (12.9 kg)

• MSRP: $7,095 USD as shown, $3,500 frame only

• www.yeticycles.com / @yeticycles • Intended use: all-mountain / enduro• Wheel size: 29"• Rear wheel travel: 140mm• 66.5° head angle• Carbon fiber frame• BB92 bottom bracket• Sizes: M, L, XL• Weight (as shown, size L w/o pedals): 28.5 lb (12.9 kg)• MSRP: $7,095 USD as shown, $3,500 frame only

It's nice to see a proper headtube badge, an often overlooked detail these days. Internal cable routing keeps everything hidden inside the carbon frame.

Frame Details

Boost spacing is in place front and rear. Fox's Float X handles the bike's 140mm of rear travel.

Suspension Design

Geometry

In a sea of bikes with increasingly long and slack geometry, Yeti didn't go too crazy when it came to deciding on the SB5.5's numbers. The 66.5-degree head angle is achieved by running a 160mm fork, which means that there's not a lot of room left for geometry manipulation by adding more travel up front. That was a conscious decision on Yeti's part – when the bike was first launched, Chris Conroy (Yeti's president) explained that they wanted it to be an all-rounder, rather than a race-specific beast solely focused on the descents.



A 437mm chainstay length and a reach of 442mm for a size large again fall in the middle of the spectrum as far as measurements go. Of course, there's more to a bike that what a handful of numbers on a screen mean, and with the SB5.5 that's especially true.



Specifications

Specifications Price $7099 Travel 140mm Rear Shock Fox Float X Fork Fox 36 Factory Headset Cane Creek 40 Cassette SRAM 1295 Eagle 10-50t Crankarms SRAM X01 carbon Bottom Bracket SRAM GXP BB92 Rear Derailleur SRAM Eagle Chain SRAM Eagle Handlebar Race Face SixC 800mm Stem Race Face Turbine 50mm Grips Yeti lock-on Wheelset DT Swiss 350 w/XM481 Boost Tires F: Maxxis Minion DHF 2.5 EXO, R: Maxxis Aggressor EXO 2.3 Seat Yeti / WTB Custom Seatpost Race Face Turbine, 150mm drop Compare to other All Mountain/Enduro/XC



Setup

Climbing

Donny Allison drops in aboard the SB5.5.

Descending

The SB5.5 is wickedly fast, nearly silent, and extremely stable, making it a potent weapon out on the trails.

It's hard to go wrong with Maxxis' Minion DHF, especially the meaty 2.5" version. Race Face's cable actuated Turbine dropper has 150mm of infinitely adjustable drop.

Component Check

Pinkbike's Take:



If the bikes in Yeti's SB lineup were members of a rock band, the SB5.5 is a shoo-in for a spot behind the drum kit, except that this isn't your run-of-the-mill drummer. It'll keep the beat and cruise right along on the approach, but when it comes time to descend the SB5.5 can throw down a mean performance, with a virtuosity right up there with Buddy Rich at his best. Now if only there was room for a water bottle inside the front triangle... - Mike Kazimer





Visit the high-res gallery for more images from this review





About the Reviewer

Stats: Age: 34 • Height: 5'11” • Inseam: 33" • Weight: 160lb • Industry affiliations / sponsors: None Twenty years deep into a mountain biking addiction that began as a way to escape the suburban sprawl of Connecticut, Mike Kazimer is most at home deep the woods, carving his way down steep, technical trails. The decade he spent as a bike mechanic helped create a solid technical background to draw from when reviewing products, and his current location in the Pacific Northwest allows for easy access to the wettest, muddiest conditions imaginable. Age: 34 • Height: 5'11” • Inseam: 33" • Weight: 160lb • Industry affiliations / sponsors: None

The build kit on our X01 Eagle bike leaves little to be desired, with a 160mm Fox 36 Float fork, a Float X shock, SRAM Guide RS brakes, and DT Swiss XM481 rims shod with a 2.5” Maxxis Minion DHF / 2.3” Aggressor tire combo. Race Face takes care of the cockpit with a 50mm Turbine stem and an 800mm SixC carbon handlebar, as well as a 150mm Turbine dropper post.All of the bikes in the SB series share similar lines, and from a distance it can be difficult to tell one model from another. That's not a bad thing, though – the curvy, swoopy carbon shapes make for frames that are just as eye-catching and lust-worthy as ever. All of the housing is hidden inside the aqua-colored carbon fiber tubes, with rubber ports to help minimize the amount of rattling.There are ISCG tabs for running a chain guide or bash guard, a feature that the shorter travel SB4.5 lacks. If there's one downside to Yeti's Switch Infinity system it's that it prevents a water bottle from being mounted inside the front triangle, which leaves the mud catching under-the-downtube location as the only option.Other notable details include Boost spacing (15x110mm up front, and 12x148mm in the rear), a BB92 bottom bracket, and integrated chainstay and downtube protection.Just like its sibling in the SB line, the 5.5 relies on the Switch Infinity suspension design for its 140mm of rear travel. The system uses two short Kashima-coated rails (courtesy of Fox Shox, who collaborated with Yeti on the design) located just above the bottom bracket to manipulate the bike's axle path.Initially, as the bike goes through its travel the carrier moves upwards on the rails, giving the bike a rearward axle path for improved pedaling performance. As the rear wheel goes deeper into its travel, the mechanism moves downwards, reducing the amount of chain tension for better big hit absorption. The carrier itself only moves a few millimeters each direction, but it's enough to have a significant impact on the way the bike's suspension behaves, especially compared to a single pivot suspension design.I've chided Yeti in the past for spec'ing narrow bars and long stems, but it looks like that's no longer necessary, and with a 50mm stem and 800mm bars the SB5.5 is ready to rock and roll right out of the box. If anything, some riders may want to trim the bars down to suit their needs, but that's a hell of a lot easier than trying to figure out how to make them wider. I ran the Maxxis Aggressor rear tire that the bike comes with for the first few weeks of testing, but once the winter rains set in I swapped it out for a DHR II in order to gain additional traction in the mud.As far as suspension setup goes, after some experimentation, I ended up settling on running the Float X with 25% sag, which ended up equating to running my body weight plus 30 psi. For the Float 36, I started off with Fox's recommended settings and adjusted accordingly to suit my riding style. The FIT 4 damper is easy to configure, with three pre-set compression settings that are changed by rotating the small blue lever, along with 22 clicks in the fully open setting that allow for further fine tuning of the fork's low speed compression.For the last several months the SB5.5 has been my go-to machine for big days in the saddle, multi-hour missions that include a mix of everything, with a strong focus on including as many long descents as possible. There's not one particular trait that's earned it this position – instead, it's a mix of attributes that make it extremely well suited for racking up the vertical.The SB5.5's outright climbing speed is reasonable, but not extraordinary – the shorter travel (and lighter) SB4.5 has the edge in that regard – but it's comfortable and well-mannered, even when faced with off-camber messes of slimy roots. On smoother logging road grinds I'd flip the Float X's lever into the middle compression setting, but for chunkier bits of trail I'd run it wide open in order to gain the most traction possible. There is a little more suspension movement in this position, but the bike still has a very satisfying surge forward when you power down on the pedals.Compared to the YT Jeffsy, which has fairly similar geometry numbers, the SB5.5's cockpit feels a little more stretched out, likely due to the slacker seat angle. This, combined with the 160mm fork can cause the front end to feel a little light on steeper climbs, but in those cases it was simply a matter of getting out of the saddle and shifting more weight forwards to stop any wandering. While the Jeffsy felt a little peppier on the climbs, the SB5.5 delivered more traction and grip in rough, chopped up sections of trail – the rear wheel stayed planted exactly where it needed to be.The bottom line? If you're solely focused on setting KOM's, sprinting up every hill like you just pounded a gallon of Red Bull with an EPO chaser, the SB5.5 probably isn't the answer. But it's not a sluggish, plodding beast either, and it'll get the job done in fine style time and time again.Yeti may have tried to make the SB5.5 into an all-rounder, but luckily, one thing they most certainly didn't do is put a governor on its downhill speed. The SB5.5 is wickedly fast, nearly silent, and extremely stable, making it a potent weapon out on the trails. It has all the ingredients of an excellent race bike, and it only took a few downhill runs to realize why it's Yeti team member Cody Kelley's bike of choice.Remember being a kid out on the playground and trying to pump hard enough to do a full loop over the top of the swingset? There were always rumors that somebody's cousin had finally cracked the code, encouraging another round of trying to go even higher, to achieve the seemingly impossible. That's what it's like riding the SB5.5 – no matter how fast you go, it feels like it can handle being pushed even harder and faster, which is motivation enough to head up for just one more run.Compared to the Trek Slash, the SB5.5 has a livelier, more precise feel. The Slash, with its slacker head angle and 10mm of additional rear travel, requires seriously steep and rough terrain to really come alive, while the SB5.5 isn't quite as single-mindedly focused, giving it a wider range of trails where it can excel. It's not quite as plush as the Trek, or Specialized's Enduro 29 for that matter, but it still has a very solid, unflappable feeling at speed.It was only on the tightest, most awkward trails, times when things slowed to less eye-watering speeds where the SB5.5 felt a touch unwieldy, require a little extra muscle to keep it moving ahead, but those instances mostly just served as reminders that the aqua-colored machine would rather be going fast at all times.The 160mm Fox 36 and the 2.5” wide Minion DHF up front are about as good as it gets when it comes to providing traction and mowing through rocks and roots, and despite the 20mm travel difference, the Float X did a fine job at keeping pace with the action occurring up front. Pushing deep into that 140mm of rear travel and then unweighting results in a satisfying boost skyward, ideal for doubling up sections of trail or popping off the lip of a jump. The rear travel has a very linear feel, without a ton of ramp up towards the end of the shock's stroke, but running 25% sag worked well to ensure that the times when I used all of the travel were entirely justified.I have zero complaints about the performance of the Guide RS brakes, but given the SB5.5's asking price I would have liked to see the RSC model spec'd – that model's pad contact point adjustment makes it easy to dial in the perfect lever feel.What is there to say about the Minion DHF that hasn't been said before? It's one of the best tires out there, and the 29” version offers up an incredible amount of traction.I didn't need to pull out the truing wrench at all during my time on this bike, and that's saying something considering how many rough miles it's seen. The XM481 rims are a breeze to set up tubeless, and the 30mm inner width allows for running wide tires at low pressure without sacrificing sidewall support.There weren't any issues with getting the Turbine post to move up and down through its 150mm of travel, although the amount of effort it takes to push the thumb lever is on the high side compared to other cable-actuated posts like the Fox Transfer or KS Lev.Shifting was crisp and quick, and there were zero dropped chains over the course of the test period. It's a matter of personal preference, but I think a 32-tooth front chainring would have been a better match to the 10-50 tooth cassette than the 30-tooth ring that's spec'd – I rarely found myself in the easiest gear, even on long, steep climbs.