Yeti Cycles

SB4.5 Turq XX1 Eagle Complete Mountain Bike - 2017

Aggressively sculpted and striking in aesthetic form, the Yeti SB4.5 Turq XX1 Eagle Complete Mountain Bike is certainly one of the most alluring mountain bikes we've feasted our eyes upon. Yet, we'd be amiss to purely focus on its beautiful lines, which turn your attention away from its dazzling trail chops and genre-blurring versatility. Further consider its stunningly light Turq carbon frame, which makes it all too easy to forget just how trail capable the SB4.5 is—and that's before you factor in the truly exceptional XX1 build kit.

The SB4.5 enjoys the steam-rolling benefits of 29-inch wheels, which make easy work of getting up and over trail impediments, such as loose rocks and gnarled roots. However, you'd be mistaken to think of the SB4.5 as some lumbering 29er, as Yeti dialed it with the flickable precision of 17.2-inch chainstays paired with a low-slung 13.1-inch bottom bracket. These numbers mean that despite its bigger wheels, it never feels unwieldy or like too much bike, even when you're slaloming around corners and dodging trail obstacles.

Paired with "only" 4.5-inches of smooth Switch Infinity suspension, your first impression would be to categorize the SB 4.5 as a big-wheeled XC machine. However, you'd be dead wrong. Its aggressively long front end with 5.5-inches of travel and 67.4-degree head tube angle fall squarely into the trail category. By relaxing the front end, it's more than eager to eat up jarring stretches of rocky terrain and conquer descents normally reserved for bikes packing another inch or so of rear travel. Despite all this, it's still efficient at pedaling and surprisingly nimble, making it one of the most versatile bikes in the shorter-travel 29er category.

Packing Yeti's famed Switch Infinity Suspension, the SB4.5 lends itself to adventurous rides with its efficient pedaling platform, yet it's never abusive when the trail turns rugged or plunges downhill. Yeti achieves this balance through a patented translating pivot that switches its direction as the bike progresses deeper through its travel, hence its Switch Infinity namesake. Yeti's engineers sought to achieve a suspension platform with distinctive anti-squat characteristics while pedaling and climbing, paired with bump-gobbling plushness that feels deeper than its limited travel suggests on the descent.

Complementing Switch Infinity's efficient pedaling platform, this particular build enjoys the feathery disposition of Yeti's Turq carbon frame. Turq carbon saves 10.4 ounces over a standard carbon frame on the SB4.5, making it ideal for competitive racers and discerning trail enthusiasts alike. Yeti's engineers achieve this feat by using the highest quality carbon, which allows them to reduce the amount of material without sacrificing stiffness. In fact, Yeti claims the SB4.5 is one of their stiffest frames (just look at those beefy seat and chainstays), meaning it seamlessly transmits rider energy into forward-surging momentum.

Leaving no detail overlooked, this crème de la crème build enjoys the crisp shifting and plentiful low-end of the XX1 Eagle 12-speed drivetrain. It's upgraded with a snappy-stiff ENVE M60 Forty HV Wheelset for incredible acceleration and precise tracking through the rough stuff. SRAM's Guide RSC brakes slow things down in a hurry, should your trail bravado cross the line into sketchy territory. It's then finished with an Ergon SME3 Custom saddle and Chris King Inset Taper headset for extra bling factor.