FAQ: What are the benefits and drawbacks of different wheel sizes?

Bike Wheel Sizes Explained

While many adventure bikes use the road bike standard 700c wheel size, you’ll see everything from small 20” wheels on cargo bikes through to large 29” mountain bike wheels. They all have their own advantages and disadvantages, and you may even see the same bike designed to work with more than one wheel size!

Smaller wheels are generally stronger, more maneuverable and better behaved under load. They can also make space for wider tyres or help keep cargo closer to the ground. Larger wheels maintain speed more easily and roll more smoothly over rough surfaces.

29er / 700c

700c and 29” wheels use the same diameter rim but are normally paired with different tyre widths.

700c is the traditional road and gravel bike size. It is commonly used with narrower tyres, although modern gravel and adventure bikes can often fit tyres around 50mm wide.

A 29er uses the same rim diameter but is designed around wider mountain bike tyres. The larger overall wheel rolls smoothly over rough surfaces, making it popular for mountain biking, touring and bikepacking.

27.5” / 650b

650b and 27.5” also use the same diameter rim.

650b is commonly found on gravel and adventure bikes, where it allows for a wider tyre without making the complete wheel too large. Some bikes can swap between faster 700c wheels and smaller 650b wheels with higher-volume tyres.

27.5” is the mountain bike name for the same wheel size and is normally paired with wider, knobbier tyres. Compared with a 29er, it generally feels a little more nimble and playful.

Cargo bike wheels

Cargo bikes use a wider range of wheel sizes depending on how the bike is designed to carry its load.

Compact cargo bikes such as the Tern GSD use 20” wheels front and rear. This helps keep the bike, passengers and cargo close to the ground, making the bike easier to balance when loaded.

The Benno Boost uses larger 24” wheels, giving it some of the stability and strength of a smaller wheel while retaining a more familiar full-sized-bike feel.

Other cargo bikes mix wheel sizes. The Yuba Spicy Curry uses a 26” front wheel for smoother rolling and a 20” rear wheel to keep the rear rack and its load lower to the ground.

Front-loading cargo bikes often take the opposite approach, using a smaller front wheel to create space for a low cargo box and a larger rear wheel for a more conventional ride feel. You can see the different designs in our cargo bike range.

One last thing - the names used for these wheels often depend on the style of bike. On a drop-bar bike you’re more likely to hear 700c and 650b, while flat-bar bikes generally use the terms 29er and 27.5”.