WTB Trail Boss 3.0 Review: 27.5+ & Bikepacking

The new WTB Trail Boss 3.0 trail tested on the rocky tracks, rugged roads, and endless pisté of southern Spain; here are our impressions after over eight hundred miles of hard riding.

In an industry of ever-evolving standards, tire size is no exception. Shortly after 29+ perked the ears of adventure seeking bikepackers, a new hat was thrown into the ring. 27.5+ offers the same expedition-relevant features in a nimbler, lighter, and some say, more efficient package: terrain expanding flotation, suspension emulating volume, and confidence inspiring, rock gobbling traction.

WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
  • WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
  • WTB Trail Boss 3.0, 27.5+ Bikepacking, B+

27.5+: The backstory

Until Interbike 2015, mid-fat 27.5” tire choices were limited to only a couple of options. In fact, the first 27.5+ tire to market was the aptly named WTB Trailblazer. But the Trailblazer came up a tad short of being a full 3” tire. At 2.8”, the slightly narrower width and lack of toothy side knobs would allow just enough chainstay clearance to enable [some] legacy 29” frames to be transformed to B+. This was an honest and honorable direction. In lieu of alienating the masses from yet another standards shift, WTB created a way to allow folks to sacrifice their dust-collecting 29ers and give plus tires a try.

WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
WTB Trail Boss 3.0 tires on the all new Marin Pine Mountain 2… shod for bikepacking!

But WTB didn’t stop there. They grabbed the promising B+ category and ran with it. Following the Trailblazer, WTB released the Bridger, a more aggressive full 3” tire. Now, their latest set of rubber, the Trail Boss 3.0, ups the bikepacking ante by delivering 3” volume, a rounded profile, and a dual compound tread with fast-rolling center knobs.

The New Boss

The Trail Boss 3.0 seems purpose built for bikepacking on mixed terrain routes. As a matter of fact, the tire’s packaging lists bikepacking as its #1 usage. Full plus tire volume serves up extra floatation, which means access to more varied terrain, as well as added suspension benefits, translating to more comfort during long days in the saddle. Harder center knobs make it a fast-roller. And its durable casing helps ensure reliability in the backcountry.

WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
  • WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
  • WTB Trail Boss 3.0, 27.5+ Bikepacking, B+

The Trail Boss is intended to be an all-around trail tire. WTB reworked the tread pattern from their original Trail Boss 2.25” by stacking a double row of tightly-spaced knobs down the centerline. The Dual DNA tread uses 50a durometer rubber on the outside knobs and a harder 60a for the center knobs. Its outer tread wraps low around the sides of the tire, in turn protecting the sidewall from puncture inducing rocks and shards… important when you’re relying on tires to pull you through remote and unforgiving wilderness.

WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
  • WTB Trail Boss 3.0, 27.5+ Bikepacking, B+
  • WTB Trail Boss 3.0, 27.5+ Bikepacking, B+

WTB doesn’t spec their casing in TPI; so all we can tell you is that the Trail Boss 3.0 uses WTB’s ‘lightweight casing’. But do not fear, it hasn’t proved too frail for middle of nowhere bikepacking purposes. Born and built for tubeless setup (TCS as WTB calls it), its casing is sealant optimized with the what WTB refers to as the correct ratio of threads to rubber. In WTB’s words this makes it “more trail worthy than other companies’ lightweight casings, without being too heavy”. It’s all about striking that middle ground. After hundreds of miles of rugged forest paths, loose and rocky roads, stretches of tarmac, and technical singletrack, we can attest to their toughness. I’ve nary a flat or rip on some of the most rocky stuff I’ve ever ridden.

  • WTB tubless, orange seal endurance
  • Orange Seal Endurance Tire Sealant

It’s also worth noting the ease of setup with the WTB Scraper rims. We initially set up these rims and tires tubeless from the comforts of a motel room using a mini pump and 2 ounces of Orange Seal’s new Endurance formula. The scrapers have an incredibly easy and secure seal, and with only 2 or 3 ounces of sealant per wheel, I never had to add any throughout the trip. The image above shows the aftermath (taken at the end of our trip).

In fact, the only real negative comment I can think of at this juncture is weight. Surprisingly, even though it’s a smaller tire, WTB actually claims the weight of the 27.5” Trail Boss 3.0 at about 75 grams more than the considerably larger 29+ tire, the Maxxis Chronicle. This extra weight didn’t prove to be a real issue for us, but we know that there are others who keep a scrupulous eye on the scales.

WTB Trail Boss 3.0, 27.5+ Bikepacking, B+

Wrap Up

Overall, 27.5+ and bikepacking seem like a match made in heaven, especially on trips in the two day to one month long variety, and in locations and situation where tire availability is not a concern – given the rarity of this tire size at present.

After 800+ miles, they’ve proven to be perfect for a mixed terrain route. For a plus sized tire, their speed and acceleration are quite impressive; they help make quick work of gravel and tarmac. They are also confident in the corners, even on loose and rocky paths, of which there are plenty in southern Spain. The Trail Boss’ tread pattern is just aggressive enough to manhandle loose rubble and technical rock gardens as well. Fortunately, we haven’t had to fully test it’s mud capabilities, but the couple times we did hit the wet stuff, traction seemed great.

To boot, they are wearing really well; I would expect these tires to easily clock 2,000+ miles. Their surprisingly generous weight may be an issue for some. But for there toughness and speed, you won’t hear a gripe from me.

  • WEIGHT: 1,125g
  • SIZE: 27.5 x 3″
  • PRICE: $67.95
  • CONTACT: WTB.com

As always, we value your longterm feedback. If you’re had a chance to put one of the products we’ve reviewed through several months of use or more, please share your thoughts below.


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