This post compares the advantages and disadvantages of 26″ and 27.5″ wheels.
The Advantages of 26″ Wheels
- Stronger Wheel
When all parameters (materials, architecture, craftmanship…etc.) are equal, smaller wheels are stronger than bigger ones because the spokes are shorter and require more external effort/stress to bend.
If your goal is to have maximally strong wheels 26″ models are better for that task. That said, the size difference between 26″ and 27.5″ isn’t substantial.
In practice, a quality 27.5″ will take just as much abuse as a 26″ model.
- Faster Acceleration
The smaller circumference of 26″ wheels makes it easier to get them up to speed.
This property is beneficial when riding in the city and/or when accelerating for a stunt when there’s little space.
- Compact
26″ wheels are slightly more compact. The smaller dimensions make it easier to store the bike in an apartment and/or to transport it in a car that doesn’t have a dedicated bike rack.
- Potentially Lighter
All things being equal, 26″ wheels are expected to be lighter because less material is required for the production of the rim and tire.
The weight difference, however, is negligible, especially in the world of recreational cycling.
- Maneuverability
Smaller wheels are more responsive and thus react faster to input. This makes them better for technical riding and the performance of stunts. If you plan on using the bicycle for such riding, 26″ wheels would facilitate the goal.
The Disadvantages of 26″ Wheels
- Limited Tire and Rim Choices
Even though 26″ wheels haven’t become obsolete yet, they definitely aren’t as popular as larger sizes. Consequently, manufacturers have a lower incentive to keep producing rims and tires for 26″ wheels.
That said, it would be inaccurate to conclude that the shortage of 26″ parts is great enough to completely rule off the wheel size.
- Lower Top Speed
Technically, the wheel size of a bike does not pre-determine its maximum speed. The maximum speed of a bicycle depends on the gearing before everything else.
For example, if a 26″ bicycle has a chainring with 44 teeth and a small cog with 11 teeth, it will offer more top speed than another unit with a 32T chainring and a 15T small cog.
However, when two bikes have the same gearing, then the model with the bigger wheels offers more speed right away.
This is easier to understand when you become familiar with the term gear ratio.
If the chainring has 44 teeth and the rear cog has 11, in that gear, the gear ratio is 44:11= 4:1.
This means that for each revolution of the front chainring, the rear cog and respectively the rear wheel makes 4 revolutions.
The higher the gear, the greater the gear ratio and consequently the number of revolutions that the rear wheel makes per one spin of the chainring.
Larger wheels are faster than smaller wheels even when the gearing is identical because larger wheels have a greater circumference and thus cover a longer distance per 1 revolution. Or in other words, a 27.5″ wheel that spins 4 times moves further than a 26″ model that does the same.
Thus, if you want maximum speed, larger wheels help with that goal.
- Harder Time Rolling Over Obstacles
Logically, smaller wheels have a harder time rolling over obstacles than bigger ones. Consequently, 26″ wheels tend to be slower than larger sizes off-road because each road irregularity presents a bigger challenge.
- Quicker Deceleration
Smaller wheels may be faster to accelerate, but once up to speed, they require more effort to keep them rolling due to their smaller circumference and mass.
- Limited Fork Choice
The number of high-end 26″ suspension forks out there is fairly slim. The situation would be even worse if dirt jumpers weren’t using 26″ wheels.
In different, there are plenty of suspension forks for 27.5″ and 29″ tires.
The Advantages Of 27.5″ Wheels
- Greater Speed Than 26″ and Better Maneuverability Than 29″
27.5″ wheels bridge the gap between 26″ and 29″ wheels.
29″ wheels offer a lot of speed and have an easy time rolling over obstacles, but those qualities come at a price – maneuverability. Larger wheels are slower to turn and make technical riding more difficult.
Meanwhile, 26″ wheels feel notably slower than 29″ but are a lot more maneuverable. 27.5″ are meant to be in-between.
- Market Support
To a large degree the MTB industry has abandoned the 26″ wheel size in favor of 27.5″ and 29″. Thus, if you want to find more high-end options, 27.5″ are the better way to go.
That said, if you don’t plan to use the bike for actual mountain biking, this point won’t affect you as much.
- Fork Support
If you want to have a maximum number of suspension forks available to you, 27.5″ and 29″ wheels are a better option than 26″.
The Disadvantages of 27.5″ Wheels
- Less Compact
When the same type of tire is used, 27.5″ wheels take up more space. This can be a problem for people living in small apartments. That said, the difference is minimal.
The table below compares the diameters of 26″ and 27.5″ wheels depending on tire width:
Tire Width | Wheel Diameter (26″) | Wheel Diameter (27.5″) | Difference | |
---|---|---|---|---|
1 inch | 609.80mm | 634.80mm | 4% | |
1.25 inch | 622.50mm | 647.5mm | 4% | |
1.4 inch | 630.12mm | 655mm | 3.96% | |
1.5 inch | 635.20mm | 660mm | 3.93% | |
1.75 inch | 647.90mm | 673mm | 3.87% | |
2.00 inch | 660mm | 685.5mm | 3.78% | |
2.1 inch | 665mm | 690mm | 3.75% | |
2.2 inch | 670.76mm | 695.7mm | 3.73% | |
2.3 inch | 675mm | 700mm | 3.7% | |
2.40 inch | 680mm | 706mm | 3.82% |
The table above illustrates that the difference in diameter between 26″ and 27.5″ wheels is quite small (4%).
It’s also worth mentioning that the final diameter of the wheel depends on the tire’s width. Thus, a 26″ wheel with wide tires could end up having a larger diameter than a 27.5″ wheel with slim tires.
- Weaker wheel
As already mentioned, 26″ wheels have the potential to be stronger. That happens only when all parameters are equal.
When To Choose 26″
26″ wheels are a good option when:
- You want your bike to be maximally compact without entering folding bike territory.
- You aren’t looking for high-end MTB experience, although that’s still possible if you go for used parts. (Those are getting harder to find but haven’t become obsolete.)
- You want a commuter with strong wheels.
- You already have a 26″ fork and frame and don’t have the funds to upgrade to a more modern MTB.
When To Choose 27.5″
27.5″ wheels are a good option when:
- You want to have an up-to-date MTB with easier options for future upgrades.
- You want to have more fork, tire, and rim options.
- You want to have a balanced bike that offers both speed and maneuverability.