Switch Infinity ran for twelve years. It was the answer to “what makes a Yeti a Yeti” — a rear triangle riding on a sliding lower pivot instead of a fixed one, patented, expensive to machine, and the reason Yeti could charge Yeti money and mostly get away with it. On August 25, Yeti retired it. The Yeti MT, a new 140mm trail bike that replaces the SB140, ships with Sixfinity instead — the six-bar suspension layout Yeti spent close to a decade developing and refining through its World Cup downhill program before it ever showed up on a bike a normal person could buy.

Six outlets published first-ride coverage within about 48 hours of each other: Bikerumor, BikeRadar, Pinkbike, NSMB, Blister, and off-road.cc. That’s an unusually wide, unusually fast read on a bike this important to the brand. Not a trickle of embargoed reviews over a month — a flood, all at once, which is what happens when a company hands out test bikes to everyone simultaneously because it’s confident enough not to control the narrative outlet by outlet.

Quick Take

Rear travel	140mm, Sixfinity six-bar linkage
Fork	160mm (Fox Factory 36 Grip X2 on higher builds)
Wheels	29in front and rear only — no mixed-wheel flip chip
Frame	TURQ series carbon only, Vectran-reinforced
Replaces	SB140 (Switch Infinity, 2014-2026)
Storage	The Cavity in-frame compartment with frame bag, top-tube accessory mount
Price	$8,000 (X0/90) to $11,500 (XX AXS); frame only $4,600
Best for:	Riders who want one bike for climbing and descending and don’t care about flip-chip tinkering
Skip if:	You want a mixed-wheel option, more adjustability, or a carbon build under $8K

Why Kill the Thing That Made a Yeti a Yeti

Switch Infinity wasn’t just a suspension platform. It was the pitch. The rear triangle floated on a sliding lower pivot instead of a conventional fixed one, moving up through the early part of the travel and back down toward bottom-out — a genuinely different way of solving the anti-squat/anti-rise problem than every other six-bar or four-bar linkage on the market. It gave Yeti’s bikes that “magic carpet” small-bump feel riders talked about for over a decade, and it gave Yeti a marketing story nobody else could copy, because it was patented.

Sixfinity gives that up in exchange for something else: independent control. According to BikeRadar’s reporting, the six-bar layout lets Yeti’s engineers tune anti-squat, anti-rise, and leverage rate separately instead of accepting whatever compromise the sliding-pivot geometry handed them. That’s the trade: less mechanical novelty, more knobs to turn behind the scenes. Yeti has been building toward this since 2016, running prototypes through 2017 and a carbon test mule by 2019, refining the kinematics through its World Cup downhill program with riders including Richie Rude before the platform ever reached a production bike. It debuted on the 160E eMTB, then spread to the MTe and LTe. We reviewed the MTe back in March and called Sixfinity’s bump absorption “significantly more than 145mm” would suggest — so this isn’t Yeti’s first Sixfinity bike. It’s the first time the platform has replaced Switch Infinity on an acoustic bike, and the MT isn’t alone in that: Yeti’s new LT enduro bike made the same switch at essentially the same time.

What’s Actually Different Between Sixfinity and Switch Infinity?

Sixfinity is a six-bar suspension linkage that controls both the rear wheel’s path and the shock through six pivot points, rather than routing the rear triangle through a sliding lower pivot the way Switch Infinity did. Here’s what changes on paper and on the trail:

1. Mechanism. Switch Infinity’s rear triangle rides on a lower pivot that slides along rails. Sixfinity uses six fixed pivots instead — no sliding parts, no rails to service.
2. Tunability. Anti-squat, anti-rise, and leverage rate can be adjusted more independently with Sixfinity. Switch Infinity’s kinematics were more coupled — change one and you were changing the others whether you wanted to or not.
3. Anti-squat numbers. Off-road.cc measured 204% anti-squat in the MT’s lower gears — high enough to explain why every outlet came back talking about climbing traction.
4. Adjustability on this specific bike. The MT gets a single progression adjuster at the lower shock mount. No chainstay-length flip chips, no geometry adjustment — the LT, Yeti’s longer-travel Sixfinity bike, gets more of that. The MT was built simpler on purpose.
5. Proving ground. Switch Infinity’s whole résumé was Yeti’s own trail bikes. Sixfinity’s résumé includes a World Cup DH program before it ever touched a 140mm trail bike — a different kind of validation, for better or worse.

Frame, Wheels, and What You Don’t Get

The MT is TURQ-series carbon only at launch — Yeti’s top-tier, Vectran-reinforced layup, no cheaper carbon option underneath it. That matters more than it sounds like: the SB140 it replaces was also sold in Yeti’s more affordable C-Series carbon, with builds starting well under $7,000. The MT skips that tier entirely, at least for now, which pushes the real-world entry price to $8,000 whether you wanted flagship carbon or not.

Wheels are 29in front and rear, full stop — no mixed-wheel flip chip. Off-road.cc flagged this directly, noting some riders will want the option to run a smaller rear wheel and simply don’t have it here. Storage is genuinely useful and not a gimmick: Yeti’s Cavity system puts a bulkhead and supplied frame bag inside the down tube, there’s a top-tube strap mount for a snack or tube, and both AirTag and Tile trackers have dedicated mounting spots. Fork duty on the higher builds goes to a Fox 36 Grip X2 at 160mm — a proven, not-experimental choice that matches the frame’s own restraint.

Six First Rides, One Consistent Theme

Read all six pieces back to back and a pattern shows up fast: the MT climbs better than a 140mm bike has any business climbing, and almost nobody had a bad word to say about how it descends. Where they differ is in how much credit they’re willing to give the suspension versus the geometry, and how much they missed the adjustability Yeti left off.

Bikerumor’s Jeremy Benson put it plainly: “The 140mm of travel is managed so well that this bike feels like it has more travel than it does.” He came away calling it close to “a quiver of one for anyone looking for a single bike that you can legitimately take out for any ride” — high praise, and the kind of line that tends to age poorly if it turns out to be launch-day enthusiasm. Pinkbike’s first ride leaned the same direction, framing the whole bike around versatility rather than a single standout trait.

Blister put roughly a month on the bike before publishing — longer than a single demo day — and the reviewer called it one of their favorite bikes they’d been on all year. The specific praise: strong pedaling efficiency for a “reasonably burly” 140mm bike, plus above-average traction under power relative to that efficiency, which is usually a trade-off, not a bonus. Blister was also honest about the ceiling — the MT climbs like a bike trying to get you to the top comfortably, not like an XC race bike in disguise, and riders chasing maximum climbing speed in this travel class have faster options.

Off-road.cc’s take was the most technical of the positive reviews and the quickest to flag a real limitation: carrying speed through chunky, high-speed terrain occasionally felt “a little jarring and a little more lairy” than expected, something the reviewer thought a suspension re-tune could probably fix. Combined with the missing flip chips and the fixed 29in wheel size, it read as enthusiastic but not uncritical — “a right hoot,” in the reviewer’s words, with a clear list of what Yeti left on the table to keep things simple.

NSMB’s read was the most measured of the bunch, and noticeably less interested in adjectives. Rather than leading with how the bike feels, it leads with kinematics — comparing Sixfinity’s anti-rise and leverage-rate graphs directly against the outgoing Switch Infinity numbers, and putting the MT’s geometry side by side with bikes like the Guerilla Gravity Gnarvana instead of just Yeti’s own lineup. That’s a first-ride piece written by people who wanted to understand what changed mechanically before deciding how they felt about it, and it’s a useful counterweight to the “quiver of one” enthusiasm coming out of the other outlets.

Yeti MT Price: $8,000 to $11,500

Build	Price
X0/90	$8,000
XT Di2	$8,500
X0 AXS	$9,800
XX AXS	$11,500
Frame only	$4,600

None of that is cheap, and none of it is a surprise from Yeti. What’s actually notable is where the range starts. $8,000 gets you into TURQ carbon and Sixfinity, but it’s also $1,000-plus more than where the SB140 entered when it still had a C-Series carbon option under the TURQ builds. If you wanted a Yeti trail bike without spending five figures, that door got narrower this week, not wider.

Yeti MT vs. the Trek Fuel EX Gen 7

The most obvious cross-shop for a 140mm, 29in trail bike with mid-fork travel and real-world versatility is Trek’s Fuel EX Gen 7, which built its own reputation on being modular and adaptable rather than mechanically novel. The Fuel EX leans on Trek’s ABP layout — proven, widely serviced, and priced to undercut a boutique carbon bike at nearly every build tier. The MT counters with a genuinely new suspension platform backed by a decade of World Cup DH development and a simplicity argument: fewer adjustments, less to get wrong.

If you want a trail bike you can reconfigure as your riding changes — geometry flip chips, travel options, wheel-size flexibility — the Fuel EX still has the edge on paper. If you want Yeti’s specific ride feel and you’re comfortable with Yeti setting the suspension tune for you rather than handing you the dials, the MT is the more focused tool. Neither is the budget pick; this is a comparison between two bikes for riders who’ve already decided to spend real money.

Who Should Buy This

Riders replacing an aging SB140 who want the same do-it-all role. The MT is built to be exactly that bike’s successor, and every first ride agrees it climbs at least as well while descending with more composure.

Anyone who wants Yeti’s ride feel without touching a wrench. The reduced adjustability isn’t a bug for riders who never used the SB140’s tuning options anyway. Set it, forget it, ride it.

Buyers who’ve already read the Yeti MTe review and liked what Sixfinity did there. The MT brings that same suspension character to an acoustic bike at less than half the MTe’s starting price.

Who Should Skip This

Riders who want a mixed-wheel option. It doesn’t exist on the MT at launch. If a smaller rear wheel matters to your riding, look elsewhere.

Tinkerers who liked adjusting geometry and chainstay length. That’s an LT feature now, not an MT one. The lower shock’s progression adjuster is the only knob you get.

Anyone hoping for a sub-$8,000 carbon Yeti. The C-Series option that used to exist under the SB140 isn’t here yet. Frame-only at $4,600 is the cheapest way into this platform right now.

The Bottom Line

Twelve years is a long time to run one suspension design as your whole brand identity, and Yeti didn’t blink retiring it. The early verdict, across six outlets and roughly 48 hours of publishing, is that Sixfinity does the job Switch Infinity did — arguably better on climbing traction, by Blister’s account, and with fewer complaints about descending composure than you’d expect from a suspension swap this fundamental. The real asterisks are the ones off-road.cc and NSMB both poked at: less adjustability than before, no mixed-wheel option, and a price floor that moved up while the design moved on. None of that is disqualifying. It’s just the cost of watching a company retire the thing that made it distinctive and replace it with something that, so far, mostly just works.

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Specs, pricing, and first-ride details sourced from Yeti Cycles, Bikerumor, BikeRadar, Pinkbike, NSMB, Blister, and off-road.cc. No test bike has been ridden by our team at time of publication.