Not long ago, mountain bikers had no choice in wheel size—26 inches was almost the only choice. However, once the 29-inch and 27.5-inch wheels were on the market, the debate among riders began and continues to this day. The 29ers was once reserved for tall riders and off-road racing, and later evolved to fit a smaller frame, and the 27.5 mountain bike has never looked so good for those who like a playful riding style. So how do you decide what is best for you? To help simplify the purchase process, below we have broken down the 27.5-inch and 29-inch wheels, including the differences in riding experience and performance, and specific bicycle recommendations for the two sizes.

27.5-inch wheels: playful, light and easy to handle

Although the 27.5-inch wheels are relatively new, they immediately gained traction in the mountain biking world because they were expected to be an effective middle ground between the old 26-inch standard and the larger 29ers. Bicycle manufacturers assure riders that they will be as fun and easy to ride as small-wheeled bicycles, while maintaining the rollover characteristics of 29ers. This "tweener" bike certainly has advantages, but unfortunately, it is not the holy grail of wheel size — we are still looking for it — and there are some inherent compromises.

Ride Experience

All other things being equal, a bicycle with 27.5-inch wheels is generally easier to ride than a 29-inch bicycle. Due to the smaller diameter, the 27.5-inch wheels are easier to pass through narrow and tricky trails and more responsive to rider input, which is especially true for smaller riders who may have difficulty controlling the larger (usually heavier) 29ers. In addition, due to its lighter weight, 27.5-inch wheels usually produce a more interesting and dynamic riding experience. You may hear riders describe them as more "fun" because they can quickly change direction and easily jump from one side of the path to the other.

However, this playful demeanor is accompanied by some compromises. First, 27.5 bikes generally feel less stable at higher speeds (or, for riders looking for faster rides, this may be a benefit). With a greater angle of attack (the angle at which the wheel meets the trajectory feature), the 27.5-inch wheel is also easier to hang on obstacles than the 29ers. To illustrate this point, imagine rolling a tennis ball down a sloping gravel path. It is likely to rebound irregularly and quickly get out of control. Now, consider rolling a larger and heavier basketball down the same path. Because of the smaller angle of attack, it will roll farther and more smoothly along the path without being thrown around by the same obstacles. If you plan to frequently walk on rugged and rocky trails, this is definitely something to consider.

Performance advantages and disadvantages

Compared with 29ers, 27.5-inch wheels generally accelerate faster, mainly because they are lighter and require less force to rotate. This might be great if your local trail includes a lot of deceleration and acceleration in sharp turns and short uphill sections. As mentioned above, 27.5 bikes also perform well on winding trails (flat and steep) with little space. In other words, 27.5-inch wheels are usually slower on straights because 29 people can build and maintain power more easily.

In terms of climbing, there are many variables to consider. We have found that 27.5-inch wheels are often more suitable for short-term and powerful climbs that require fast turns and technical operations. They are also lighter when climbing hills and provide better overall acceleration. However, if you want to climb gravel roads or flat, straight single lanes, then we will pay tribute to the 29er because it can better maintain speed.

29-Inch Wheels: Confidence-Inspiring and Stable at Speed

29-inch wheels, also known as 29ers, did not cause much sensation when they were introduced 20 years ago. Originally paired with short trips and clumsy cross-country bikes, they quickly became associated with soft terrain. But now, many years later, the landscape has changed dramatically. From recreational mountain bikes to all-mountain crushers, you can find 29ers. It is foreseeable that they have both advantages and disadvantages, but they can be a good substitute for 27.5-inch wheels.

Ride Experience

Mainly because of their lower angle of attack, 29ers are easier to climb over trail obstacles than 27.5-inch wheels. This means smoother riding and less effort to keep the bike running. In fact, people usually equate 29 people with a giant truck, which is certainly a compliment when you stare at tree roots and rocks or slippery conditions. These characteristics also result in a bicycle that is stable and clearly inspiring, especially on the more technologically-rich monorail track.

However, the increased stability does bring some significant compromises. Due to the increase in weight and size, 29ers can be more challenging to maneuver on narrow and tortuous trails, which is especially true for smaller riders who may struggle to entangle the bike. In addition, despite the bicycle companies doing their best to ensure that 29ers can adapt to all heights, the equipment is still large. Finally, for many shorter riders (under 5'2" or so), they are usually too many bikes.

Performance advantages and disadvantages

One of the most obvious performance advantages of 29-inch wheels is their ability to maintain power, which usually translates to higher speeds. This is especially true when a trail is mostly straight and there are few sharp turns to interrupt your flow. And we're not just talking about downhill sections-the 29ers also do a good job of maintaining climbing momentum (of course, once you have established some speed). A big part of this equation is traction: 29ers have a larger contact area with the ground, which means there are more rubber contact trails at any given point (and most importantly, when climbing, cornering, and braking). This may only be noticed by the most demanding rider, but this is why you often see professional mountain bikers with 29-inch wheels.

Nevertheless, while 29ers are clearly good at maintaining speed, they are not good at building it. In short, heavier objects require more effort to move, and 29-inch wheels are no exception. So while the lure of higher speeds may be tempting, if your footprint includes a lot of deceleration and acceleration, it may be worth investigating 27.5-inch wheels.

27.5 and 29 Plus (Mid-Fat): Improved Traction and Stability

Plus" or medium fat bicycle tires are wider than traditional bicycle tires (2 to 2.5 inches), but narrower than fat bicycle tires (4 to 5 inches). Designs in this category use both 27.5-inch and 29-inch wheels, although the former is currently the more popular choice. No matter which wheel size you choose, medium fat tires are best for those who want to improve traction, stability and off-road comfort. However, more rubber brings more weight, and compared to traditional tires, bicycles are heavier and less flexible. That said, there are many good mid-weight bikes on the market, including Salsa’s Timberjack 27.5+ and Santa Cruz Chameleon’s 27.5+ variant.

If you have your own ideas, please contact us(sales1@gofastbicycle.com) to discuss and provide you with customized services.