Ultimate Guide to Choosing the Best Gravel Bike Tire Size and Tread Pattern

Introduction

Gravel bicycles have become increasingly popular in recent years as more cyclists look for versatile bikes that allow them to explore beyond the pavement. Gravel grinders provide access to a world of unpaved roads and trails, making tire setup an important consideration for this new breed of bicycles. Two key factors that determine how a gravel bike will handle the varied terrain it may encounter are tire size and tread pattern.

Tire Sizes 

Tire width is often discussed before gravel races. Even a difference of a few millimeters can make a significant impact for professional riders who need to ensure precise specifications. However, for most riders, the priority is to have comfortable and grippy tires rather than just focusing on speed.

When it comes to gravel bikes, it is usually advisable to opt for wider tires. The reason for this is that a wider tire can be ridden at a lower pressure, which results in better comfort and grip. Moreover, wider tires have a higher volume, with more air between you and the ground, which can enhance puncture protection.

If you spend a lot of time on the road or race on tightly packed gravel, then tires that are 35 to 37mm in size are likely to be a good fit for you. On the other hand, if you ride on rugged trails, encounter plenty of mud, and spend little time rolling on tarmac, then tires that are 47 to 50mm in size would be a good fit. 

However, if you're looking for an all-rounder tire that can handle a wide range of different surfaces without having to swap out your tires, then a 40 or 42mm gravel tire is the one to go for. While it may not be the fastest rolling tire or deliver the greatest traction, it should perform well across the board.

When considering larger sizes, it's essential to check if the frame and fork can accommodate the width.

Tread Patterns

The tread pattern of a gravel tire plays a crucial role, much like with MTB tires, as it determines how and where the tire can be utilized. An aggressive and highly grippy tread pattern provides excellent off-road traction and confidence, but it's less efficient when it comes to speed. On the other hand, a smooth tread pattern is designed for speed and efficiency. There are also tires that are designed to strike a balance between speed and traction. Such tires often have a uniform pattern, consisting of similar knobs that span the entire width of the tire, resulting in a predictable tire with consistent cornering grip.

Slick gravel tires are essentially wider versions of road tires. They have a low-profile tread that is ideal for cyclists who mainly ride on pavement, smooth dirt, and gravel roads. These tires are the fastest option for gravel bikes on paved roads, but they may not be the best choice for rougher terrain. The lack of raised knobs in the tread pattern means that they have reduced rolling resistance over smoother surfaces, which is perfect if you tend to ride on paved routes with the occasional gravel detour. These tires usually have a slight file tread pattern that provides extra grip on light dirt paths. The slick texture of these tires means that there is more rubber in contact with the ground for better grip than knobby tires in drier, smoother conditions.

Semi-slick Tread

A semi-slick tire features a strip in the center which is smooth and has raised knobs on either side to provide extra grip when turning. The smooth section in the middle helps decrease rolling resistance on paved surfaces, so you can save energy. The additional texture on the sides of the tire helps you maintain control on looser terrain. This tire type is perfect if you frequently ride long distances on paved surfaces but still want to feel confident when switching to loose dirt or gravel routes.

All-rounder Tread

If you're searching for a gravel tire that can do it all, then the type with a dual tread pattern is your best bet. This type of tire has a more aggressive texture than semi-slicks, with low-profile, densely packed knobs covering the central stripe and larger side knobs for better cornering. This versatile tread pattern is an excellent compromise between semi-slicks and extreme gravel tires, allowing you to explore almost any gravel route on the map while still being fast enough on paved sections. If you spend most of your time on loose gravel and dirt tracks, with paved roads being used sparingly, then an all-rounder gravel tire is the way to go.

Extreme/Mud Tread

These gravel tires have larger knobs to dig into trail surfaces and prevent mud buildup. Aggressive gravel tires are recommended for backcountry riding or bikepacking when trail capabilities are more crucial than efficiency on pavement. If you ride through rough gravel, mud, or some singletrack, these beefier gravel tires offer better traction and grip in the corners. The specific knob shapes are often specially designed to clear away muck buildup, enabling riders to maintain traction in sticky mud. Extreme gravel tires exhibit characteristics similar to XC mountain bike tires.

Choose On Different Terrains

To make it easier to understand, we will use a scale from 1 to 10. 1 represents a 100% paved, asphalt surface, suitable for a road bike, while 10 represents a 100% mountain bike terrain, suitable for a full-suspension MTB.

Conclusion

In summary, choosing the right tire size and tread for your needs optimizes your gravel bike's performance. Wider tires provide comfort off-road, while narrower profiles suit firm paths. Aggressive knobs excel in mud but hamper speed, whereas slicks roll fast but lack grip.

The best all-rounder balances these factors with a dual-pattern 40-42mm tire. It handles varied conditions without swaps while letting you explore wherever trails lead. Ultimately, pick tires matching your primary 1-10 terrain scale to fully unlock your gravel bike's versatility. With the right rubber, every route is within reach.