SB5.5 T-Series X01 Eagle Complete Mountain Bike 2018
The popularity of long travel 29ers has boomed in recent years as riders have caught on the benefits of wagon wheels and manufacturers have figured out how to make the geometry work for trail and enduro applications. The big wheels simply roll faster, preserving more of your hard earned momentum and getting less hung up on rocks, roots, and chunky terrain in general. With balanced geometry and a good suspension platform, long travel 29ers climb and corner with the best of them too. The Yeti SB5.5 checks all the boxes with plush yet efficient Switch Infinity suspension, a stiff carbon frame, and geometry that loves to go fast up and down the mountain. It's a proven EWS-winner at the hands of Richie Rude, chosen for high speed courses with long, pedally transfers. If you're looking for a versatile all-mountain bike that carries speed everywhere, with smooth suspension that stays planted on the roughest lines, all while remaining efficient enough to be pedaled on all-day epic rides in backcountry, the SB5.5 T-Series X01 Eagle Complete Mountain Bike is a worthy addition to your stable of bikes.
The heart of this bike is Yeti's Switch Infinity suspension, which is among the best we've ridden. It's plush throughout the 140mm of rear travel, offering a smooth ride quality that makes it feel like you've got more travel than the numbers dictate. It maintains impressive traction across chattery small bumps and square-edged hits alike, with enough ramp to confidently soak up sizeable drops. Paired with a 160mm Fox fork up front, the SB5.5 is unstoppable when gravity takes over and the trail points down.
Climbing abilities are equally as important, and Switch Infinity doesn't disappoint. The beauty of this design is the translating main pivot, aka the Switch Infinity link. The link moves upward in the beginning of its travel, creating ideal anti-squat characteristics for efficient pedaling that minimizes energy lost to the suspension. We found ourselves leaving the shock in open mode for most climbs, except for sustained grunts on buff fire roads. As the suspension moves deeper into its travel, the link switches direction and moves back downward, providing buttery smooth suspension action for successive bumps and harder hits.
The SB5.5's balanced geometry is another element of the bike's success. The 66.5-degree head angle paired with a 51mm offset fork is stable on descents and high speeds, without making the bike feel sluggish on tamer trails and climbs. The reach and wheelbase are generous, but not overly long, providing a good balance between stability and maneuverability. The 17.2in chainstays are short but not too short, which is what Yeti wanted, helping the rear wheel stay tracked through rugged terrain. A low-slung top tube and fairly short standover help you lower your center of gravity for more control on descents and while cornering.
This model uses Yeti's TURQ-series carbon fiber, consisting of the highest quality materials Yeti can get their hands on, delivering a fine balance of strength, low weight, stiffness, and compliance. This makes for a ride that's fully composed over rough terrain, and surefooted when you're stepping on the gas and railing high-speed corners. By using high modulus carbon fiber, Yeti is able to shed roughly 400 grams compared to the Carbon-series frames while maintaining the same levels of durability.
The component spec on this bike doesn't leave much to be desired. Top-tier Fox Factory suspension with low-friction Kashima coating yields a plush ride, with a good range of adjustments to dial it in for your individual weight, riding style, and the terrain at hand so you can charge the hardest lines with confidence. You'll need some solid brakes to control all that momentum and the DH-worthy Code RSC's do the job nicely with plenty of outright power as well as modulation that lets you fine tune your speed without immediately breaking traction. Acceleration duties are handled by a SRAM XO1 drivetrain that offers precise, reliable shifting and a wide gear range, with a 50t bailout gear that helps you get up steeper climbs that might normally require dismount.
- Long travel 29er that excels at all-mountain riding and enduro
- 5.5in of travel works well both up and down the mountain
- Switch Infinity design is remarkably plush and efficient
- Geometry is stable at speed but not sluggish on tamer trails
- TURQ carbon is stiff, strong, and light with a refined ride quality
- XO1 Eagle drivetrain and Code RSC brakes offer superior performance
- Top-tier Fox Factory suspension damps the trail for a plush ride
- SB5.5 has been proven at the EWS level by Richie Rude and Cody Kelley