Yeti SB120 Review: A 120mm Trail Bike Built for Efficient Speed

Introduction

The Yeti SB120 is a 120mm travel trail bike that takes the place of the SB115 in the range, but it is a different machine underneath the paint. Frame travel is close to its predecessor, yet the geometry and the suspension have been reworked, and the bike carries the revised Switch Infinity link that first appeared on the SB160.

The most visible change is in the numbers. Reach has grown from 450mm to 475mm on a size Large, the head angle is slacker, and the front of the bike now runs more travel than the rear. A 130mm Fox 34 fork is paired with a Float DPS shock across the range, which gives the SB120 a more balanced front to rear feel than a short travel race bike.

Yeti offers six sizes from XS to XXL, five complete builds and a frame only option, so there is a reasonable spread of ways into the platform. What follows covers what changed, how the bike is put together, and where it makes the most sense.

Geometry, Sizing and Who It Suits

Despite the similar rear travel to the SB115, the SB120 is not pitched at cross country or downcountry riding. It is aimed at riders who want a trail bike that pedals efficiently, holds speed across rolling terrain and stays composed when the trail points downhill.

Yeti has also made the geometry size specific. Seat tube angles range from 71.1 degrees to 73.2 degrees depending on frame size, while the effective seat tube angle, measured from the bottom bracket to the centre of the saddle rails, stays constant at 76.5 degrees. Chainstay lengths grow with the frame, from 433mm to 443mm, which Yeti says maintains proportionality across the size range. Taller riders get a steeper physical seat tube, which is intended to make the move from seated to standing feel more natural, and a longer rear centre to keep the weight distribution balanced between the wheels.

Main Strengths

Efficient Pedaling and a Stable Rear End

The Switch Infinity system, built for Yeti by Fox, places the rear pivot on a shuttle that rides on Kashima coated stanchions and travels up and then down through the suspension stroke. The intent is to separate anti-squat, the force that counteracts pedal bob, from the shock leverage curve, so the bike can pedal well without the usual compromises. The SB120 runs 11 percent progression, with leverage dropping from 2.84 at the start of travel to 2.52 at the end, and each shock is custom tuned in house.

Early trail time in the Quantock Hills showed how still the rear end stays under power. The linkage looks almost static when viewed from the saddle, which points to a relatively high anti-squat figure, and the result is a bike that feels efficient on smooth climbs and lumpy, technical ones alike. Traction does not suffer for it either. Steps, rocks and roots can be felt through the saddle, but the edge is muted, and the rear tire keeps hold of the ground. On flatter trail the suspension moves more under pedaling loads, though never to the point of reaching for the shock lockout lever.

Descending Confidence and Mid-Stroke Support

The longer, slacker geometry gives the SB120 noticeably more stability and confidence than the SB115, and the suspension carries a generous amount of mid-stroke support. That makes the bike rewarding to push hard into natural corners and easy to pop off trail features, with a lively rather than dead feel underfoot. It is not an isolating ride. Plenty of trail feedback comes through the bike, which suits riders who like to know exactly what the tires are doing.

Things to Consider Before Buying

Those same traits define the bike’s limits. With 120mm of rear travel and a deliberately communicative suspension feel, the SB120 is not a cloud smooth ride, and on really chunky, square edged trails the rear wheel is more prone to catching than a longer travel bike would be. Riders who prioritise maximum plushness, or who spend most of their time on steep and broken descents, may be better served by a bigger travel option.

It is also worth being honest about terrain. The SB120 rewards riders who mix climbing with flowing descents and who value efficiency as much as capability. If your riding is mostly lift assisted or gravity focused, the case for this bike is weaker.

Frame Details and Finishing Touches

The refinements are subtle but practical. The belly kink at the bottom of the frame is less pronounced, which improves ground clearance, and the chainstays sit slightly higher off the ground. The Switch Infinity link and shock are held tighter within the frame, freeing up room for a bottle, while the seat tube is shorter and still accepts longer drop posts. Yeti claims overall frame stiffness has increased without losing compliance, and tire clearance has been improved as well.

The linkage that drives the shock has been reworked too. It is more compact, which helps reduce standover height, and it is stiffer than before. Standard size Enduro Max bearings now sit in the linkage rather than in the front or rear carbon triangles, held by floating collar axles. Yeti says this arrangement reduces tolerance gaps to virtually zero and keeps the assembly tight over time. Cables run through internal tubes in the rear portion of the frame, with clamped stops at the head tube and by the bottom bracket to keep rattles to a minimum. Down tube protection is a two piece item, as wide as the frame’s carbon tube, with a rubberised inner layer and a replaceable hard plastic outer layer that can be removed to help with cable installation. There is a threaded bottom bracket shell, ISCG5 mounts, alloy inserts that are co-moulded into the frame rather than bonded in, and a SRAM UDH hanger, so replacement should be straightforward at almost any bike shop.

Build Options and Pricing

Five models are available alongside a frame only option at $4,300. Three builds use the higher modulus TURQ series carbon, and two use C series frames. Every complete bike comes with a Fox 34 fork with 130mm of travel, a Float DPS shock, four piston brakes and 180mm rotors front and rear. The range topping model is specified with a Fox Factory shock, SRAM X01 AXS and SRAM Level Ultimate brakes at $12,100. The most affordable complete build is the C2 at $6,300, which comes with a Fox Performance shock and Shimano SLX for both drivetrain and brakes.

Buying Advice

Match the bike to the riding you actually do. The SB120 makes the strongest case for riders who want a trail bike that climbs efficiently, feels lively underfoot and still has enough composure to be ridden hard on descents. If your trails are smooth and rolling, or you mix long climbs with technical singletrack, the package lines up well.

Sizing deserves a moment of thought, because the geometry is not uniform across the range. Larger frames get longer chainstays and steeper physical seat tubes, so a rider at the top of a size band may find the proportions change as they move up a size. If you are between sizes, consider whether you want the extra stability of the larger frame or the quicker handling of the smaller one.

On builds, the frame only option at $4,300 suits riders with a parts bin or strong preferences, while the C2 at $6,300 is the most accessible complete bike and still carries the same frame layout and travel. Stepping up to a TURQ build buys the higher modulus carbon and a higher specification, which is worth it if you want a lighter frame and premium components from the start. Whichever route you take, budget for the fact that this is a premium platform with premium pricing.

Conclusion

The Yeti SB120 takes a familiar amount of rear travel and rebuilds the bike around it: longer and slacker geometry, a revised Switch Infinity link, size specific chainstays and a set of frame details that make living with the bike easier. It pedals with unusual efficiency for a trail bike, stays supportive through the mid stroke and asks the rider to engage with the trail rather than float over it. If that character matches how you ride, it is a convincing and genuinely capable trail bike.