I'll admit it: I like fat tires.
I'll admit it: I like fat tires. (Photo: Taj Mihelich)
Bike Snob

27.5+ Tires, the Goldilocks of the Mountain-Bike World

Rumors of my favorite tire size’s death are greatly exaggerated. (I hope.)

I'll admit it: I like fat tires.

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Recently I was catching up on the latest bike marketing propaganda on a popular cycling site when I came across the following:

The perennial wheel- and tyre-size debate never seems to disappear, and we reckon for 2019 it will still feature heavily over a post-ride drink.

While fat tyres seem to have largely disappeared, and true plus widths never quite caught on, from the 2019 bikes we’ve seen so far it looks like 2.5in and 2.6in rubber might just make its mark.

Wait, what? Plus-sized tires “never quite caught on,” really? As the owner of no fewer than two (2) bicycles with 27.5+ wheels, I suddenly felt self-conscious, like the kid who shows up at school in last season’s sneakers.

So could this be true? Was I really rolling around on a dated, outmoded wheelsize? I headed immediately to the website of a certain popular bicycle brand with a reputation for being something of a plus-sized gorilla in the industry. Poring over their roughly 4,000 different mountain bike offerings, it was admittedly difficult for me to make sense of their various model names and proprietary terminology (“6Fattie” sounds like a six-patty sandwich from Burger King, not a tire size), but it did in fact appear there were now only five (5) bikes with plus-sized tires. (“Plus” meaning a width of at least three inches.) Surely if this company was no longer cashing in on the chubby tire craze, then there was no craze left to exploit, and I was now like those poor saps still riding around on that same company’s taxi-themed fixies after the bottom fell out of the track bike market back in 2010.

This was a vexing development, because I have found the 27.5+ tire size to be nothing short of fantastic. I love the Velcro-like traction on climbs. I love a tire that swallows roots like a bursaphelenchus xylophilus. (That’s a thing that eats roots, apparently.) I love not having to deliberate over my bike choice because I’ve got one (well, two) that can handle pretty much everything. And more than anything, I love enjoying many of the benefits of suspension without having to necessarily resort to a costly, finicky, and obsolescence-prone suspension bicycle.

Of course, when you start suggesting that all-terrain cycling can be enjoyable without suspension, the baggy-shorts set gets very touchy. Indeed, when I dared suggest that riding rigid bikes can be awesome I received actual email about how I was putting people in danger by telling them that it’s okay to go mountain biking without using suspension. As it turns out, while traditionally the roadies are the ones who have a reputation for being persnickety, it is in fact mountain bikers for whom a half-degree of head angle here or there is a source of outrage. To them, the notion that rigid bikes are awesome is apostasy. This can make the most terminal cassette-flossing, tan-line-obsessed, Rapha-swaddled roadie seem like a stoner on a beach cruiser in comparison.

Obviously there is a permanent place for suspension bikes in the vast cycling firmament, just as there is for time trial bikes and recumbents and trials bikes and all manner of contraptions that have been engineered for a particular use case. (“Use case” is technical jargon for “use.”) At the same time, the bicycle industry seems to react in a roundabout way when it comes to riding off-road. Common wisdom holds that the gravel bike was a response to the limitations of the road bike, but wasn’t it just as much of a response to the limitations of all those over-suspended mountain bikes ill-suited to the long haul? Basically with gravel bikes and “road plus” and all the rest of it, we’ve just reinvented the rigid mountain bike and added drop bars—which is pretty much exactly what John Tomac was riding almost 30 years ago.

Given the timeless allure of riding simple, efficient bikes off-road, I’m puzzled by these dire prognostications when it comes to plus-sized tires, which are a major boon in that department. For months, I’ve been riding a Jones Plus SWB Complete (the stock tires are 27.5 x 3.00), and while it may not be the first bike I’d choose for rides on the most extreme ends of the road/mountain bike spectrum, it’s absolutely fantastic for pretty much everything in between. It’s the kind of bike you can hop on with no particular destination in mind and know that no matter where you wind up it’s got you covered. This is of course a function of the bike’s overall geometry and design, but a key aspect of that design is its ability to clear those apparently out-of-fashion plus-sized tires.

You don’t need a particularly aggressive tread pattern to get plenty of traction out of a three-inch tire on the trails, and thanks to this, it will also roll acceptably well on the road, which is especially great if you’re the sort of person who enjoys riding to the ride. Essentially, the versatility of a bicycle increases proportionately to its tire width. (The two lines on the chart do diverge eventually, but that happens somewhere between 3.0 and Full Fat.)

Sure, I’ve read complaints that plus-sized tires require you to pay extra attention to #whatpressureyourerunning so that they’re not too bouncy, but since when are cyclists afraid of dialing in their tire pressure? Cyclists seem to be able to rationalize the purchase of $159 tire pressure gauges even without plus-sized tires. And yet, while plus-size is now uncool, apparently 2.6 is pefectly au courant. Go figure.

Most absurd of all is that wheel and tire size is framed as a “debate” in the first place. It’s like debating what size underpants everybody should wear. I mean hey, size down if you want, but I’ll keep enjoying the extra wiggle room.

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Lead Photo: Taj Mihelich