Yeti’s ‘Infinity Link’ equipped ‘SB’ range of bikes now contains more than four members: the SB5 (and SB5 plus) SB6, SB4.5 and the SB 5.5 reviewed here. I don’t blame you if you can’t figure out what each bike is, but I will tell you that the SB (Super Bike) 5.5 (inches of travel) is the big-hitting, 140mm rear travel (160mm front travel), 29 inch wheeled bruiser aimed at enduro shredders. I enjoyed reviewing the SB5.5, not least because it suited my bike preferences well, but also because I had recently ridden the SB6 (27.5 wheels/150mm travel), which proved a useful comparison and helped expose an interesting difference...
The frame I reviewed was Yeti’s top-of-the-line ‘Turq’ carbon version, which saves around 400 grams over Yeti’s lower-level carbon framed 5.5s (Yeti indicates the Turq frames are a little stiffer than the standard frames too, though conversely are also not quite as resistant to impact damage). The 5.5 does of course feature a tapered head tube, internal cable routing, post-mount brake mount, and Boost axle spacing. The only missing feature is a lack of bottle mount inside the front triangle (I consider the bottle mount under the downtube a good spot for tools and a tube inside a bottle-shaped container, but I wouldn’t be sticking my mouth on a bottle that’s spent time in the firing line of anything that flings up from the front wheel).
The Yeti 5.5 is one of the best bike specs I have seen. Aside from the 132mm WTB Volt seat fitted (too narrow for me), there isn’t one item I’d want to swap out. The rear shock is the new Fox Factory DPX2 (love it) with a Fox Factory 36 up front (love it too). A SRAM X01 Eagle drivetrain, SRAM Guide brakes, and the piece-de-resistance: DT Swiss wheels with 32 J-bend spokes, DT’s uber-reliable star-ratchet freehub, and 30mm internal width DT alloy rims with a Maxxis Aggressor 2.3 (business) out back and a Maxxis Minion DHF 2.4 (party) up front. In addition, a Fox Transfer dropper and Thomson bar and stem completed the package. This kit isn’t cheap, but there’s very little that could be improved in terms of performance.
I tested a size large 5.5. It features reasonably ‘modern’ numbers: a 66.5 degree head angle and moderate 442mm reach, along with not-long-but-not-the-shortest 437mm chainstays. Similarly, a not-the-lowest 346mm BB height meant fewer pedal-strikes than some bikes, but I didn’t ever lack for stability – win-win. The 73.6 seat angle sounds a bit slack on paper to me, but in practice I could get the fore/aft seat position where I want it relative to the BB without slamming the seat all the way forward, which was nice. Fit wise the large 5.5 felt bang-on for my 180cm height. Though a 160mm fork on a 29er means, no matter that the 5.5’s head tube is really short, the stock bars might not be low enough for some shorter riders on smaller frames. Still, a short rider could always fit a flat (or negative-rise) bar to solve that issue.
It took me a while to find the right shock pressure. Not because it sucked, but for the exact opposite reason: because the Switch Infinity equipped 5.5 rides very well within quite a broad range of pressures. I was happy right off the bat with my first go based on a rough sag measurement, but after experimentation found that an incredibly sweet sweet-spot that offered excellent traction, great support and just enough bottom-out resistance was a good 25 psi lower than I started with. This was particularly interesting to me, because when I rode the 27.5 wheeled 150mm travel SB6, I never got the rear suspension to behave quite like I wanted it to. With the 2017 SB6, no matter how much pressure experimenting I did it was both more chattery over small stuff than I wanted, yet at the same time it didn’t provide adequate bottom out resistance. It seems likely I needed a bigger volume reducer in the shock of the SB6, so I wonder if Yeti has specced the new 2018 DPX2 shock with a volume reducer that fits my needs perfectly?
Regardless of what was the cause, the rear suspension action on the 5.5 was a mix of smooth like butter and sweet like sugar (which seems like it might be fudge or caramel, but I’m not a baker, so I’m not sure). Pedalling performance from the Switch Infinity link was excellent – a supportive mid-stroke meant steep climbs were met with a shock that stayed propped up (rather than excessively sagging back under the increased rear-biased weight like some bikes do), even without using the shock lever. The level of anti-squat provided a near-ideal balance between pedal-pep and roots/rocks erasure when climbing. I never needed the shock lock out when climbing or indeed on gravel roads. In fact, rather than as a ‘road-speed-lever’, if anything, the shock compression lever might find its only use when visiting a fast, smooth trail with big jumps, for extra pop. SRAM’s 12 speed Eagle provided ample climbing gears and the 5.5 would arguably have been better off with more top-end sprinting gears with a 32 tooth ring, rather than the 30 tooth fitted.
At speed, the combination of active suspension and big wheels meant the 5.5 felt incredibly composed ripping around rooty corners, noticeably more so than the Yeti SB6 I rode earlier this year, which was no slouch itself. Those not-too-short chainstays and slack-enough head angle contributed to being able to stay centred and still keep weight on the front end; I didn’t feel the need to be moving about to find the proper place to be. Initiating a turn with the back-end (scandi!) was also nice and easy on the Yeti. The front doesn’t lift up for lofting through a bomb-hole as effortlessly as some, but the trade-off is worth it. That firm-ish middle stroke also meant that when pushing into corners, my feet felt properly supported. Jumping was intuitive with just enough ramp-up progression in the shock to prevent harsh bottom outs when overshooting a landing.
It’s worth noting the 2018 Fox 36 was also an incredibly sweet and smooth performer; it was noticeably more supple over small bumps than last year, and I’m told this is thanks to the new internal arrangements featuring a revised (bigger) negative chamber and fewer seals. What that meant was fantastic grip, great support when braking hard down steep descents, and just-right bottom out resistance with the stock number of volume reducers, for my 82kg ride-weight.
What about any little niggles? There were no cable rattles, no clattering plasticy sounds when rocks hit the (armoured) downtube, no creaking or squeaking from any pivots or bearings (or Infinity Link), no fading brakes, no buckled wheels. Admittedly though, no usable water bottle mount. Lots of pros, just one con.
Who is this bike for? I’m going to say, quite a wide range of people. For example, a rider who loves his Yeti ASR 100mm travel 29er got on this bike for two days and loved it. He was surprised at how slow it wasn’t uphill (he was still fast uphill on it). And aggressive/DH based riders will be more than happy with its descending chops. If you ride mainly on smooth terrain, the capabilities of the 5.5 aren’t going to be utilised, but on the other hand, the downsides are not huge: the pedaling performance is such that you could put a semi-slick out back and the Aggressor up front, and a rider not looking to win the XC World Champs could race well at a local XC event on the 5.5. Obviously though, it’ll be most at home on hard-out enduro courses and rocky, fast, and challenging terrain.
Would I change anything? Price. I’m not just being clever here; if I could have it all, I’d want the cheaper frame (which features the same stiffness and strength, but weighs an insignificant amount more that makes no difference to how the bike rides) and this exact spec. But that’s not an option. You have to buy the pricier frame to get this kit stock. Which partly explains the not insignificant price of $10,400 for our review bike. There’s no way around it – like other boutique brands, top-end Yetis cost a lot of money. On the other hand, I loved the geometry, the suspension performance was outstanding and the kit was flawless. Added to all this is Yeti’s five-year warranty, which goes a long way to clawing back some value for this Yeti. If you have the wherewithal, the 5.5 will not disappoint.
Yeti SB5.5 Key Specs
- Frame: Turq Carbon Fibre
- Rear Travel: 140mm
- Front Travel: 160mm
- Shock/Fork: Fox Factory DPX2/Fox Factory 36
- Drivetrain/brakes: SRAM XO1 Eagle/SRAM Guide
- Wheels/tyres: DT 350/Maxxis Aggressor and Minion DHF
- Weight: 12.9kg (w/o pedals)
- Price: $10,400
Images & Words: Jason Turner & Carl Patton
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