The SB4.5c builds off the success of its 27.5-inch brother, the SB5c, by incorporating Switch Infinity rear suspension into a 29er package. One of our test riders said, “This bike makes me a better rider than I am.” That’s high praise for a 29er full-suspension bike without the full-XC bug. But this Yeti inspires confidence. With big wheels and 4.5 inches of rear travel, paired with a 140-millimeter Fox fork, it makes straight-lining technical sections a breeze.
Yeti’s Switch Infinity rear suspension is the standard-bearer for plush rear travel that’s active on descents and stable on climbs, and it feels right at home on the 29er platform. The rear suspension can, if anything, be accused of being a bit too XC-oriented for what we would consider a trail bike, but with some fine-tuning, it’s possible to find a plush setting that’s equally capable on descents. Yeti also offers a trail-tuned shock that’s more supple on descents; ride a little higher pressure in it and you’ve got a fully-capable XC setting.
The 1x drivetrain and Fox Factory squishy bits make this about as fuss-free as trail bikes get. The full-carbon frame is plenty light, too: The full build weighs in at just a hair over 26 pounds, which is more than respectable for a big-wheel bike.
It won’t ever be the most responsive bike out there. Big wheels generally translate into somewhat sluggish steering, and while the SB4.5c is likely one of the most responsive 29er trail bikes, at the end of the day it’s still a 29er. The 67.4-degree head tube and 437mm chain stays make it whippable, but not 27.5-inch whippable. Think of it more as a steamroller than a Porsche and you’re set up for a lot of fast, fun descending and stable climbing. That said, it is surprisingly lithe on sustained and technical climbs.
One of our testers found himself looping out on those technical climbs, though, so riders in between sizes may want to err on the larger side. Otherwise, the SB4.5c comes closest to XC climbing combined with enduro descending than any trail bike we’ve tested in recent memory.
Component Highlights: SRAM X01 drivetrain; SRAM Guide RSC brakes; Fox Float Factory DPS shock; Fox 34 Factory 140mm fork; DT Swiss 350 Boost wheels