26″ vs 29″ vs 27.5″

26 vs 29 vs 27.5 (commonly mislabeled as 650b): which wheel size is the best? That seems to be the million dollar question these days and if you’re unsure about which size to go with, you’re definitely not alone. Looking to finally leave the confusion behind once and for all? Read on.
If you’ve been biking at all in the last 30 years, you know that 26″ wheels have been the industry standard for quite some time. They are the old stand-by.  In fact, of all the people that currently own an adult-sized bike, most of those bikes have 26” diameter wheels. A lot of these complete bikes are the bikes we grew up with, and many of them have sentimental value. They’re quick and agile on the trails, and they seem to have a seemingly endless supply of varieties in the mountain biking world that you may not even have heard of: Freeride (FR), Downhill (DH), All-Mountain (AM), Cross Country (XC), Dirt Jumping (DJ), Four Cross (4x), Enduro (ND), Marathon (XCM), and Bike Trials, just to name a few.

However, in 2001 Gary Fisher Bikes introduced the very first production 29″ diameter wheel bike, and shortly thereafter it was dubbed the “29er”. 29ers took a couple years to take off, but in the last five years they have arguably been the best selling wheel format in the mountain bike industry. Why have they been so popular, you ask? For starters, they have a few advantages over their 26″ brethren:

  • Each pedal revolution results in more distance is traveled, hence your effort results in going farther
  • Larger tires means more air, which means a more cushioned ride
  • The angle at which the tire attacks the terrain is smaller, which means obstacles are smoothed out

Let me explain that last one a little bit more. Picture your everyday sedan, like a Toyota Camry. Let’s say you want to take your Camry out in the woods to roll over a few logs. That would be a bad day at the office, no? Now picture your favorite Monster Truck, and go roll over those same logs. Pretty simple, right? The 29er is the Monster Truck of the bike industry, to be sure.

That sounds like a lock, right? I should just go buy a 29er and be done with it, you say? Not so fast, there are some drawbacks too:

  • Monster truck wheels make it harder to navigate tight and twisty trails, so be aware of what types of trails you frequent
  • Larger wheels mean larger frames, which means more weight, which is weight YOU have to pedal around
  • Big wheels also mean longer spokes, which means heavier riders can taco wheels much easier
  • Longer suspension components (more than 100mm of travel) on a 29er can make the big wheels feel unwieldy

Commonly mislabeled as the 650b, 27.5″ is actually a tire size that’s been around for quite a while, almost 100 years, primarily in Europe. There are a number of countries, Sweden and France being the most notable, where there are still many 27.5″ bikes in use. They are/were primarily used for commuting, hauling cargo, and utilitarian purposes. Does that mean they were relegated to the streets alone? On the contrary, there was a French Cycling Club in the 1950’s that developed an early version of mountain biking on 27.5″ bikes fitted with moped suspension and handlebar-mounted shifting. So 27.5″ isn’t entirely foreign to dirt!

This wheel size didn’t have staying power in the US over the years, and that’s why many people out there had never heard about it. But starting sometime in 2009 it really has become the hottest topic in the mountain biking industry. The bike retailers and suppliers are not exactly sure what to do with it, I think. Some suppliers and retailers have jumped on the bandwagon (always trying to keep their
customers happy), and they are making and stocking frames, forks, wheels, and tires to feed the new frenzy.

Others are more reticent, because they’re not so sure we need a third wheel size in the mountain biking industry. Even down at the local level, some bike shops are trying hard as it is to keep 26″ and 29″ goods in stock, and some shop owners are cringing at the thought of yet another standard to keep in stock and potentially gather dust on their shelves. All that being said, the industry is being a little slow (in my opinion), in ramping up 27.5″ production.  However, in hindsight the industry as a whole is moving a lot faster than it did when adopting 29ers so they are definitely learning something.

Here’s my current breakdown of production Complete Bikes:

Entry Level bikes ($400-$1000):

26er: hardtails short and long travel and short travel full suspension

27.5″: Hardtails short travel (these are currently hard to find)

29er Hardtails short travel


Mid-Level bikes ($1000-$2000)

26er: racy (lighter and short travel) hardtails, racy short travel full suspension, long-travel full suspension

27.5″: Hardtails long travel, long travel full suspension

29er: Short travel full suspension

High-Level Bikes

Lighter versions of all of the above wheel sizes, with more exotic frame and component choices,
using more Titanium and Carbon Fiber for rigidity and weight savings


Now that you have some background, why are 27.5″ bikes becoming more popular now? There’s a few reasons, most notably among the disadvantages to 29ers stated above. Riders want another option that:

  • Isn’t as heavy
  • Can allow for longer suspension
  • Is more maneuverable on tight switchbacks
  • Can still have bigger-than-26”-wheels for rolling over obstacles

As an added bonus (especially for those of us on a tight budget), some are discovering that their 26″ frames they already have can fit 27.5″ wheels, which in many cases brings new life to their “old and tired” 26er bikes. So does that mean that 650b is the Holy Grail of mountain bike wheel sizes? I really don’t think so. I really believe it’s personal preference based on your local trails and riding style. Best way to find out for sure? Go out and ride!