

If you happened to find yourself on Yeti's website during a bout of aimless internet wandering, you'd have to look under the cross-country category to locate the SB4.5c. With 4.5” (114mm) of rear travel and 29” wheels that designation makes sense, that is until you realize that the bike has Yeti's long-and-low geometry, a 140mm fork, and a 67.4-degree head angle, numbers that suggest there might be more to this turquoise machine than initially meets the eye.



There are two complete builds available, the GX version for $5,599 USD, or the XO1 version we tested that retails for $6,899. Riders who wish to build their own ride from the ground up will need to part ways with $3,400 for the frame and shock.

SB 4.5C Details



• Intended use: XC / trail

• Rear wheel travel: 114mm

• Wheel size: 29"

• Carbon fiber frame

• BB92 bottom bracket

• Sizes: S, M, L, XL

• Weight (as shown, size L w/o pedals): 25.75 lb (11.68 kg)

• MSRP: $6,899 USD, $3,400 frame / shock only

• www.yeticycles.com / @yeticycles • Intended use: XC / trail• Rear wheel travel: 114mm• Wheel size: 29"• Carbon fiber frame• BB92 bottom bracket• Sizes: S, M, L, XL• Weight (as shown, size L w/o pedals): 25.75 lb (11.68 kg)• MSRP: $6,899 USD, $3,400 frame / shock only

There's no shortage of clean lines on the SB4.5c. The 29 x 2.2" Maxxis Ikon is on the narrower side, but luckily there's room to fit meatier 2.3" tires.

Frame Details

A 12 x 148mm thru-axle keeps the rear wheel secured into place. A BB92 bottom bracket, downtube protection, but no ISCG tabs to be seen.

Suspension Design

3 Questions With Yeti

There's quite the travel difference between the 114mm rear end and the 140mm fork, but it works extremely well out on the trail. Were the bike's geometry figures originally developed with that configuration in mind?

What was the reasoning behind not including ISCG 05 tabs?

We're starting to see more bikes that can accept both 27.5+ and 29” wheels. Was that a consideration during the design process of the SB4.5?

Geometry

Specifications

Specifications Price $6899 Travel 114mm Rear Shock Fox Float Factory DPS Fork Fox 34 Factory 140mm Boost Headset Cane Creek 40 internal Cassette SRAM 1180 10-42 Crankarms Race Face Turbine 30t Bottom Bracket Race Face BB92 Rear Derailleur SRAM X01 11-speed Chain SRAM 1130 11-speed Shifter Pods SRAM X01 11-speed Handlebar Easton Haven carbon 740mm Stem Easton Haven 55mm Grips Yeti lock-on Brakes SRAM Guide RSC Hubs DT Swiss 350 Rim DT XM401 Tires Maxxis Ardent 2.4 f / Ikon 2.2 r Seat Yeti / WTB Custom Seatpost RockShox Reverb Compare to other All Mountain/Enduro/XC



Setup

The SB4.5c's rear suspension design provides plenty of grip while still remaining bob-free during out of the saddle pedaling.

Climbing

Descending

Even with 'only' 114mm of rear travel, the SB4.5 is capable of handling seriously rough terrain, thanks to the combination of its big wheels, well managed rear travel, and dialed geometry.

Component Check

Pinkbike's Take:



Speed freaks will rejoice at the SB4.5c's capabilities, but even riders who prefer to cruise along at a more subdued pace will appreciate the handling and suspension feel that Yeti have baked into this turquoise machine. It's a lively trail bike that doesn't balk when faced with more technical terrain, and I'll admit that I felt more than a twinge of regret when it was time to box up the SB4.5c and return it to its Colorado home. - Mike Kazimer





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





About the Reviewer

Stats: Age: 33 • 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: 33 • Height: 5'11” • Inseam: 33" • Weight: 160lb • Industry affiliations / sponsors: None

The SB4.5c's full carbon fiber frame shares a similar look to the other models in Yeti's line of Switch Infinity equipped bikes, with the same swoopy styling and generous amount of standover clearance. The cable routing further adds to the clean, modern look, tucking the brake, derailleur, and dropper post routing out of sight inside the frame.The frame is designed to work solely with 1x drivetrains – there's no front derailleur mount to be seen – but unfortunately, Yeti also decided to forgo ISCG mounts. Clutch derailleurs and narrow-wide chainrings work very well, but it would be nice to at least have the option to run a small upper guide to completely eliminate the chance of a chain falling off.Boost spacing is in place at the front and rear of the bike, which provides enough clearance for a 29 x 2.3” tire in the back, and room for something even bigger in the front. There are a number of bikes on the market that can run either 29" or 27.5+ wheels, but the SB4.5 is intended to be a dedicated 29er.The location of the Switch Infinity suspension system means there's no room for mounting a water bottle cage inside of the frame, but there are mounts on the down tube. That's better than nothing, but be aware of what you've been riding through before blindly taking a swig from your bottle.By now, the Switch Infinity suspension design doesn't look quite as radical as it did when it was first announced, but it's still different enough to raise questions from riders who haven't seen it out in the wild.For those who aren't unfamiliar with how the system works, it relies on 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 in 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.As far as maintenance goes, there's a grease port on each of the rails, and Yeti recommends lubing the system every 40 hours to ensure everything stays buttery smooth, a procedure that can be performed in mere minutes.Yes, we will often play with various aspects of our suspension spec with our internal testing team and professional athletes. Our intention with this bike was to give it a bit more travel in the front and ensure this was an aggressive XC/trail bike. The result is a bike that climbs extremely well and is just as capable on descents. In fact, we would say that the most common response from first time riders on the SB4.5c is that they knew it would climb well, but they never expected it would descend as well as it does.Again, our intention with this bike was to design a truly aggressive XC/trail bike. As we looked at the advantages vs. disadvantages of adding the ISCG 05 tabs, we felt that the majority of riders on this bike would be inclined to run a 1x setup without a chain guide, so it made sense to keep it clean and simple for the SB4.5c. We were also working on the SB5.5c, our longer-travel 29er, at the same time we were developing the SB4.5c. We knew the SB5.5c would be the most aggressive enduro-focused bike of the two 29ers and spec’d the SB5.5c with the ISCG 05 tabs, among other components, to clearly equip that bike for the toughest enduro tracks in the world.No, it was not a consideration. We get this question quite often and, for now, designing bikes with multiple wheel size options just isn’t our direction. We simply haven’t found the ride quality we are looking for with bikes that can accommodate multiple wheel sizes. For us, the compromises outweigh the benefits.In its stock configuration, the SB4.5c is aimed squarely at the XC / trail side of the spectrum, but I'd love to see Yet offer a version with a slightly burlier spec. As it is, riders who live in wetter climates, or who frequent steep, loose trails will probably want to swap out the Maxxis Ardent / Ikon tire combo for something more substantial. The same goes for the 740mm Easton Haven carbon bars. If that's your preferred length, you're in luck, but it's about 40mm too narrow for my tastes.Have you ever seen an asphalt milling machine in action? You know, that tank-treaded contraption that chews up pavement and then spits it out into a dump truck? Well, that's the image that regularly popped into my head when I was aboard the SB4.5c – it simply eats up the trail, and if you're not careful, before you know it you'll be three hours away from home on what was supposed to be a quick spin around the block.The SB4.5's handling on the climbs feels a little calmer than the SB5, a bike that takes off like a jackrabbit at the merest hint of a hill, but that doesn't mean that the bigger wheeled bike is any less capable. It still has the chops to clamber up just about everything short of a vertical wall, and even then there's still a chance it might make it to the top. There's just enough rear suspension movement to keep the rear wheel on the ground without slipping, and plenty of support to keep it from bobbing or wallowing.The SB4.5's uphill prowess is on par with Trek's Fuel EX, but Yeti's Switch Infinity system has less movement when standing up and putting the power down, a trait that I prefer, and one that allowed me to keep the Fox DPS shock in the Open position in the second compression setting for both climbingdescending.Even with 'only' 114mm of rear travel, the SB4.5 is capable of handling seriously rough trails, thanks to the combination of its big wheels, well managed rear travel, and dialed geometry. Of course, as usual, there's the caveat that you can't go charging headlong into a rock garden the same way you would on a 160mm enduro monster, but I still came away extremely impressed with just how forgiving of a ride the SB4.5c provided.In fact, if I didn't know better I would have guessed that there was 130mm of rear travel on tap – it was only the occasional 'clunk' of the shock reaching the end of its travel, usually off of a drop into a hard G-out, that would remind me of the rear end's limits. Compared to Kona's Process 111, the bike that deserves credit for kicking off the short travel aggressive 29er movement, the Yeti has a more plush suspension feel, with better small bump sensitivity at the beginning of its travel. That helps provide more grip during cornering, and smooths out the chattery, potentially jarring sections of trail.There's a speed demon hidden somewhere under the SB4.5c's carbon skin, and going fast is its forte. Now, making a 29er that goes fast in a straight line isn't an extraordinary feat, but to create one with such a beguiling mix of liveliness and stability is especially impressive. It'll whip in and out of tight turns without missing a beat, and just as easily take on a steep chute pockmarked with awkward holes and chunky rocks.The SB4.5c's geometry is thoroughly modern, but not overly radical - there are 29ers out there with chainstays shorter than 437mm, and head angles slacker than 67.4-degrees, but all of the SB4.5's numbers add up to create something that's incredibly versatile, no matter how wild or tame the terrain. And anyone who still believes the old myth that '29ers can't jump' should take this bike for a spin – it takes minimal effort to get it airborne, and the sub-26 pound weight only serves to make it that much easier to pop towards the sky.The only issue I had with the SB4.5's downhill performance was the fact that it can get kind of noisy at higher speeds on rough trails. Even with an integrated chainslap protector, the design of the chainstay means that when the chain hits it at a certain angle it echoes loudly, alerting riders and other forest creatures that you're rocketing down the trail towards them.Fox's 140mm 34 was smooth and silent throughout the test period, and felt well matched to the Float DPS shock. Even though there's more than 20mm difference between the front and rear suspension the bike still felt very balanced.The X01 rear derailleur's clutch didn't seem particularly strong, which may have exacerbated some of the chainslap noise I experienced. Otherwise, with the exception of one dropped chain, the 1x11 drivetrain was trouble free, with crisp, accurate shifts even after being doused in pouring rain and splashed by deep mud puddles.The XM401 rims remained dent and wobble free even after a few months of abuse. I wouldn't mind if they had a wider internal width, but they still provided enough support for running 2.3” tires without any burping or rolling off the rim.As for the hubs, I do have a couple of gripes. The first is related to the Centerlock to 6-bolt adaptor that was used to mount the SRAM rotors. I'd rather have a dedicated 6-bolt hub – there's much less chance of the system coming loose or developing play. I'd also prefer a 36 or 54 tooth star ratchet rather than the 18 tooth version that was spec'd. Once you've become accustomed to quicker engaging hubs, the difference is readily apparent when going back to something with 20-degrees between points of engagement.