On The Plus Side

“Down the trail, look! It’s a fat bike. It’s a mountain bike. It’s…a plus-size bike?” Cycling’s latest trend has arrived in the form of the plus-size tire.

It all began a few years ago (in 2012 to be exact) when Surly introduced the world to the Krampus and its good friend, the Knard. When the first production 29+ bike and tire became available, most of the cycling world sat back in anticipation to see if this weird, new, gargantuan tire standard would catch on. And catch on it has. This past year’s Sea Otter show saw the latest and greatest plus-size offerings from some of the biggest names in the industry—both in the 29+ and the 27.5+ varieties. As more brands toss their hats into the plus-size ring, consumers are increasingly realizing the benefits of having more rubber between them and the dirt.

Grip It. Grip It Good.

Plus-size tires fall somewhere in between a traditional mountain bike tire and a fat tire. By definition, they are between 2.8" and 3.25" when mounted to a 40–50mm wide rim. The combination of a wide-profile rim and the girth of a plus-size tire creates a larger contact patch for the tire to connect to the dirt, which we all know equates to one thing: traction. Plus-size tires aren’t just between fat tires and mountain tires in terms of width though. They also fall right in the middle when it comes to tire pressure as well. Add that to the extra grip the tire itself offers, and you’ll be stuck to the trail in the gnarliest of conditions.

Ride Over Anything

Ok, so maybe the wide rim/big tire combo actually equates to two things. Plus-size tires (provided you have a frame that is compatible with them) give the rider an abundant amount of stability and comfort over something like a 29 x 2.25" or 27.5 x 2.25" set up. Let’s talk about confidence first. With a wider footprint under you, you’ll feel like there’s not much you can’t ride over—and you’d be right. While out on a ride, you’ll likely find yourself going through corners faster and riding trails that you’ve never had the gumption to take on before. Now let’s talk about comfort. Remember that lower tire pressure? That comes in to play here, too. In addition to extra grip, lower pressures also provide a bit of extra cushion on rough and rocky trails.

More Bang For Your Buck

When plus-size began to gain traction in the industry, it had many people worried and up in arms. Another new standard? Another issue with compatibility? On the contrary, depending on a rider’s current frame, these new plus-size options might actually make it more versatile. If you have a 27.5+ frame, a set of standard 29er wheels will easily fit. Surly’s Instigator is a 26+ frame that can also accommodate a standard 27.5" wheelset. All of these are great options if you’re looking to get a little faster handling and better acceleration out of your current frame. That sounds like two bikes in one to us! Fat bikes allow you to take advantage of plus-size wheels and tires, as well. If you’re looking to get a little more use out of your fat bike, throw a 27.5+ setup on it if you typically ride 26 x 3.8", or 29+ if you normally ride 26 x 4.8". This will drop weight from your fat bike with a minimal loss of traction on dirt, so you can shred the gnar with ease all year round. A few—albeit not many—29ers on the market are compatible with 27.5+. There’s a small chance that you’ll be able to fit a 27.5+ wheelset with some 2.8" shoes mounted to it, provided you can still have a minimum of 6mm of clearance at the chainstay, seatstay, and chain while in the lowest gear.

Will It Last?

With so much buzz around plus-size tires, many people are wondering the same thing: Does the plus-size trend have staying power? Or will it go the way of the LaserDisc and Crystal Pepsi. Early indications are that this is more than just another cycling fad. As more bikes, forks, tires, and rims become plus-size friendly; as more brands jump on the bandwagon; and as more consumers realize the benefits they offer, it’s fairly safe to say that plus-size tires will be around for some time. Will they ever completely replace traditional tire sizes? Probably not, but they will work in unison with them to provide riders more options with fewer bikes, thanks to the ability to run multiple wheel sizes in one frame.

Check out more plus-size tire tech here.

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