The terms 650b and 27.5 inches are actually referring to the same thing – a particular size of a mountain bike wheel. 650b or 27.5 inches wheels are a medium between 26in mountain bike wheels and 29-in wheels. This size of wheel fell between the 26 inches wheels that were standard at the time and the 29-in wheels that were becoming increasingly popular. So, 650b and 27.5in became popular terms to describe this in-between size. 

650B wheels offer quick acceleration and the light feel of 26 inch mountain bike wheels, but with more towards the extra stability, rolling resistance, smoother feel, and enhanced traction of 29 inches wheels. These wheels are the best choice for riders who want an agile, easy maneuverable bike but can still handle rough terrain. 650b tires tend to be narrower than 29er tires, which can make them more susceptible to punctures

Many riders wonder what the benefits of using these smaller diameter wheels are and if they are worth the switch. In this guide, we will explore the pros and cons of 650b tire size for both mountain and gravel bikes, so you can decide if this is something you might want to consider for your next bike purchase. Also, we have listed some of our best 650b wheels size mountain bikes to help you take a loot what features these tires offer. 

Advantages of 650b Wheels in Mountain Bikes

650b Wheels in Mountain Bikes

  1. 650b wheels allow for lower air pressures, providing a more comfortable ride. They also tend to run high-volume tires, adding to the comfort factor.
  2. The smaller build of 650b wheels will be lighter than the often gangly-looking 29ers. This makes them easier to handle on the trail and gives you more control over your bike.
  3. 650b wheels offer an ideal compromise between 26-in and 29-in wheels. They are not as slow and sluggish as the latter, but they are also not as twitchy and difficult to control. 
  4. Because 650b wheels are becoming increasingly popular, there is a growing selection of tires, rims, and other designed components. This means that you can customize your bike to suit your riding style and needs.
  5. 650b wheelset have a shorter spoke length than 29ers, which makes them stiffer and more responsive.  
  6. The smaller diameter of 650b tires also means they are less likely to get ‘hung up on obstacles such as roots and rocks. This gives you a smoother, more enjoyable ride overall.
  7. 650b wheels have a lower rolling resistance than their larger 29er counterparts. This makes them faster and easier to pedal, especially on longer rides.
  8. Finally, 650b wheels simply look nicer than 29ers! They strike a balance between the burly build of a 29er and the elegant looks of a 26-in bike, and this aesthetic is certainly appealing to many riders.

Disadvantages That Come with 650b Wheelset

650b wheelset is a relatively new trend for gravel bikes. While they have some benefits, there are also some significant disadvantages. One of the biggest drawbacks is that 650b wheels don’t smooth out trail undulations and 700c wheels. This can make for a rougher ride, particularly on longer outings.

Since 650b tires are new, they have less aftermarket support for tires and other accessories. This can make it more difficult and expensive to build up a 650b-specific gravel bike. Also, 650b wheelsets are hard to find, and when you do find them, they’re often more expensive than 26″ or 29″ wheelsets. 

650b Tire Size is Better For What Riders?

650b Tire Size

Each wheel size has its distinct advantages and disadvantages, making it hard to choose which one is right for you. However, 27.5in wheels have emerged as a popular option for many riders because they provide a balance between the speed of 26-in wheels and the stability of 29-in wheels. These wheels are often more compatible with the frame geometry of smaller bikes, making them a good choice for riders with a smaller stature. 

But a 650b wheelset may not be the best option for everyone. One key factor to consider is rider height. If you’re on the shorter side, then 26-in wheels may be a better fit. If you’re taller, you may find that 29-in wheels offer greater stability and roll over obstacles more easily. Another thing to keep in mind is tire width. Wider tires can provide extra traction and comfort on rough terrain, but they may also make your bike harder to handle on tight turns.

Check out Some of the Best 27.5 Wheel Size Mountain Bikes

  1. Gravity FSX 27.5 DLX24 Full Suspension Mountain Bike 
  2. Neffice Mountain Bike Mens 27.5 Inch Wheels
  3. Mongoose Colton 27.5 Inch Wheels Adult Mountain Bike 
  4. Hiland Aluminum 27.5 inch Wheel Mountain Bike

Some Last Words

650b vs 27.5 in wheels can be an ideal choice for gravel and mountain bikes because they offer a good balance of speed and stability. They are also less affected by wind resistance than larger wheels, making them ideal for off-road biking. However, note that they can be more difficult to find tires for and may not fit all frames. So, make sure when you buy it, only the manufacturer has an exchange or return policy so that you can re-order. Or simply go to a bike shop with your bike and try out the wheel size yourself. 

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Frequently Asked Questions 

Q1. What is the difference between a 27.5 and 26 inch mountain bike? 

The difference between 27.6 inch and 26 inch mountain bikes is that the former has about one-and-a-half-inch larger wheels. This results in a bike that is more stable and can roll over obstacles more easily. 

Q2. Why choose a 27.5 inch over a 29 inch mountain bike?  

Some best 27.5 inch mountain bikes offer better features than 29 inch options in several ways. These bikes tend to be lighter and more agile, making them easier to control on tough terrain. They also tend to have shorter chainstays, improving maneuverability and making it easier to keep the bike balanced.

The smaller wheels of a 27.5 inch mountain bike provide better acceleration while riding and easier climbing, making them a good choice for riders who want to go fast on the trails. However, best 29 inch mountain bikes still have their advantages, such as rollover ability and better stability at high speeds. 


I am David, one of the best contributing tech editors. I have written more than a million words about thousands of bikes and equipment. To make sure my hobby turned profession inspires others, I have also penned 3 bike-related books and have given interviews to many YouTubers.