All about gravel tires

It is well known that gravel bikes have conquered cities, trails, and everything in between. It is also well known that a gravel bike needs the right tires to meet the diverse purposes of use. The fact that there is now a large selection of gravel tires is no secret either. But how do you find the right tire for your gravel bike?

Here you will learn everything you need to know about gravel tires. For example, which tire sizes fit a gravel bike. Or which tire tread suits your plans. And whether puncture-proof tires are important to you. And so on. By the way, today people mostly talk about the “bicycle tire”, but it is also not wrong to continue calling this bicycle part bicycle casing .

What tire size fits your gravel bike?

Basically, there are three sizes to consider when choosing tires for your gravel bike, just like any other bicycle.

There is the wheel size. It specifies the diameter of the wheel. Usually, on a gravel bike, this is 28 inches (equivalent to 622mm). Less commonly, there are 27.5 (584mm) or 29 inches.
There is also the tire width. Depending on the purpose of use, tires with a width of 32 to 55mm are mounted on gravel bikes.
Both together make up the tire size you need to buy for your gravel.

Tire width and tire diameter for gravel bike tires

Gravel bikes particularly often have 28er wheels, the tire width ranges between 32 and 50mm. Images © Pirelli

To start, let's find out which tires actually fit your gravel bike:

How much tire clearance does your gravel bike have?

To buy the right tires for your gravel bike, you need to know which tire width and tire diameter fit into your bike frame.

Every bicycle has a manufacturer-recommended tire clearance (or in English “clearance” or “tire clearance”). The tire clearance tells you how wide the tires can be so that they can rotate freely in the rear and fork. Additionally, every bicycle is built for a specific wheel size.

So, on most bicycles – including gravel bikes – you can only ride wheels of one size, but you can mount tires of different widths.

Some bikes also offer the possibility of mounting wheels in different sizes. This works, for example, with the “Terra” gravel bikes from Orbea . If your gravel bike has this option, you can find out in the section "What sizes are available for gravel tires?" how the tires affect the riding characteristics and choose which riding characteristics are important to you. With a bike that does not offer this option, you must decide when purchasing the bike.

If you do not find any information in the product description or manual of your gravel bike, the rule of thumb is 4mm minimum distance of the tire to the frame.

In what size are gravel tires measured?

Choosing the right bicycle tire is unfortunately a bit complicated because there are different units of measurement for wheels, tubes, and bicycle tires, namely French sizes, English sizes (in inches), and ETRTO or ISO sizes.

Often you don't have to deal with multiple sizes when looking for the right bicycle tires because certain tire sizes have become established depending on the type of bicycle. On road bikes, you will often find French tire sizes, on MTBs it is often measured in inches/English tire sizes, and trekking bikes and city bikes usually have ETRTO sizes (or ISO) specified.

As if that weren't complicated enough, the matter is unfortunately made a bit more confusing by the different approaches to measuring the tires. While the outer diameter is measured for inch/English and French tire sizes, the ETRTO specification calculates with the inner diameter at the tire bead. But there are tables that help you compare the sizes.

Which tire size for which bicycle?

French sizes → Road bikes
ETRTO size specifications → Trekking bikes and city bikes
Tire sizes in inches → Mountain bikes

For gravel bike tires, the trend is towards French tire sizes. But because the purpose of the gravel bike covers exactly the intersection of all bicycles, you may have to deal with all three size systems when looking for the right gravel tires.

If you mainly ride your gravel bike in the city, it may be that you will buy all-weather tires with ETRTO specification.
If you want to ride off-road, tires from the MTB area in inches may be the right ones.
If you are looking for a sporty rolling behavior for fast rides on asphalt, you will deal with road bike tires and French tire sizes.

Frequently (but not always), gravel bikes are equated with road bikes when it comes to tires. That's why you often find the French tire sizes as a manufacturer's specification for the tire clearance of a gravel bike or as a size specification on the tires themselves.

Since they are often found on gravel bikes, here's a quick explanation of the French tire sizes - they consist of the following measurements:

approximate outer diameter

x tire width

General NOTE ON TIRE HEIGHT; A, B, or C

A common tire size on a gravel bike would be 700x35C, so the tire has about a 700mm (70cm) outer diameter, 35mm width, and C corresponds to about 39mm.

What sizes are available for gravel tires?

There are different wheel sizes on the bike, but most gravel bikes run on one of two possible sizes, they have 28-inch wheels or 27.5-inch wheels. This also makes selecting the right tires much easier.

The diameter of the wheels

Gravel bikes, thanks to their road bike heritage, mostly have 28-inch wheels, but there are also 27.5 or 29-inch diameters (i.e., particularly thick 28-inch tires). Depending on what your frame allows, the appropriate wheels must be mounted and tires in these sizes fitted.

The wheel sizes for gravel bikes as a table

	27.5-inch wheels	28-inch wheels
ETRTO	… -584	… -622
Inch/inch	27.5x…	28x…
French	650x…	700x…

(the dots here replace the tire width)

What influence does wheel size have on a gravel bike?

In the world of off-road bikes, wheel sizes have been hotly debated for years, sometimes smaller tires are considered better, then again only large tires are used. If you can't decide at all, buy a bike with a mullet setup, i.e., two different tires at the back and front, or a frame that offers the possibility to mount different tire sizes. But which tire is better on a gravel bike?

Larger tires on a gravel bike?

Large tires (or better: large wheels) are always good for optimal propulsion on gravel, so if you want to cover distance and do it quickly, you should opt for larger tires. The steering can feel a bit more sluggish with larger wheels, but the bike holds its line better, running more stably overall. When you're off-road, it can be quite interesting that large wheels roll over obstacles better than small ones.

Smaller tires on a gravel bike?

Smaller wheels make your gravel bike not only more agile, but also accelerate faster. However, this reduces efficiency on the track slightly. Smaller wheels offer another option: depending on the allowed clearance, you can use tires with a larger volume on smaller wheels. Such a setup provides more cushioning, better grip, and improved puncture resistance.

In addition to the technical advantages and disadvantages, the height of the rider also plays a role in choosing the right tires for a gravel bike. Small frame sizes fit small wheel sizes, especially tall riders need a large frame size and thus larger wheels.

The tire width on a gravel bike

Regardless of the wheel size, you can use different “thicknesses” of tires. From 32 to 50mm are the common tire widths on a gravel bike, and the width has a significant impact on the bike's riding characteristics, especially on cushioning and efficiency. But the susceptibility to tire punctures is also affected.

The tire width on a gravel bike as a table

	32mm	35mm	37mm	40mm	47mm	50mm
ETRTO	32-...	35-...	37-...	40-...	47-...	50-...
Inch	…x1.25 (or …x 1 ¼)	…x1.35	…x1.40 (or … x 1 ⅜)	…x1.5 (or …x1 ½)	…x 1.75	…x 2.0
French	…x 32B/C	…x 35B/C	…x 35B/C	…x 38B/C	…x 45C	–

(the dots here replace the wheel diameter)

What influence does tire width have on a gravel bike?

The width of your gravel tires is directly noticeable, whether you use wider or narrower tires, it has an impact on the riding characteristics, comfort on the bike, and puncture susceptibility.

Wider tires on a gravel bike?

The more air in your gravel tires, the more cushioning they provide, so wide tires ride more comfortably. Wider tires also have more surface area on the road, offering more traction and grip. On the other hand, you exert more effort to overcome rolling resistance when more tire surface “sticks” to the road. Lastly, wide tires are naturally heavier.

Narrow tires on a gravel bike?

If you're in a hurry, you should opt for narrower tires, less rolling resistance, less weight, and excellent efficiency are the clear advantages here. However, the bike loses off-road capability as the tire width decreases. The narrower the tires, the smoother the road surface should be. Also, cushioning is less effective with narrow tires.

The right tire profile for your gravel bike

The tires of your gravel bike have a "pattern," and depending on the intended use, more or less of it. This pattern, aka. tread pattern, makes the tires either faster or more off-road capable. Thick knobs grip better on poor surfaces but require more energy. Smooth tires roll efficiently but need flat surfaces.

If you ride cross-country
If you ride on poor or loose surfaces
If top speed is not so important to you
If you are out and about in bad weather and mud

… you should prefer tires with a lot of tread .

Gravel tires, all-rounders with a lot of tread

Fancy a little more tread? Then such a gravel tire is the right choice. Image © Pirelli

If you are on somewhat paved roads , like on paved bike paths, on forest roads, etc.
If you mainly ride your gravel in the city and in everyday life
If you are out in different weather conditions

… you should mount tires with moderate tread .

If you appreciate speed
If you ride on asphalt
If you mainly ride in dry weather

… then less tread, i.e., slicks, is best.

Keep in mind that more tread makes your tires heavier.

Gravel bike tires, slicks with little tread

Does your gravel bike need puncture-proof tires?

A gravel bike is often out for long distances, the touring bike genes practically scream for multi-day tours! The further you move away from civilization, the safer you are with puncture-proof tires. Especially if you want to use your gravel for bikepacking tours with a lot of luggage , puncture-proof tires can be a real asset. A heavily loaded bicycle is more prone to flat tires, and puncture-proof tires save you a lot of trouble. Puncture-proof tires have a rubber layer or a fabric insert built into the tires that protects against punctures or cuts.

The disadvantage of puncture-proof tires: They tend to cost a bit more, and often weigh a bit more due to the protective layer in the carcass. But for more gravel fun without tire punctures, this is gladly accepted! Even if you are riding with puncture-proof tires, you should not forget the spare tube on longer tours! An alternative is a puncture protection insert, we have a test report for you in the blog .

Are tubeless gravel tires better?

Tubeless tires are of course also an option on the gravel bike. If your wheels are tubeless compatible, you can convert a gravel bike to tubeless tires.

The advantages of a tubeless setup are numerous. You can ride tubeless tires with less air pressure, which is comfortable and offers better grip. Additionally, this makes the tires less prone to punctures. The sealant closes small holes directly and without much effort on your part, and you often don't even notice smaller punctures. The bike becomes lighter without tubes, which is also an advantage.

Of course, there are also disadvantages: Tubeless rims and tires are usually more expensive and the installation takes longer than setting up a system with tubes.

We have a guide for converting to tubeless for you here in the Bike Blog. Although the individual steps are shown on the MTB here, they work similarly for gravel on the whole.

> Discover tubeless tires

Convert gravel bike to tubeless, tire with sealant

What else should you know?

Reflective stripes: If you want to ride your gravel bike on public roads, it must have the required safety equipment, which includes side reflectors. If the tires have reflective strips, you don't have to worry about this!
The rubber compound: Tires are made from different compounds, also referred to as the “compound”. Each manufacturer has its own “secret recipes”. There are compounds that “stick better”, offering more grip and hold. Others are particularly suitable for wet conditions, while others roll better. To find the right tire material for your purposes, it is worth comparing products from different manufacturers. The properties of different models from the same manufacturer are also very informative and a comparison helps you in your selection!
Do you have to use special gravel tires? Nowadays, all manufacturers offer special gravel tires. They are particularly suitable for the diverse demands placed on a gravel bike, but they are not a must. If you're chasing speed records, you can opt for road bike tires, but if you're more interested in off-road adventures, MTB tires from the XC or marathon range are a good option. You shouldn't dismiss all-weather city tires either. If your gravel is mainly ridden in the city, all-weather city tires are worth considering.

↪Gravel Bike Tires & Accessories in the Online Shop↩

Gravel Bike Tires | Tubes | Gravel Bike Wheels

The right tire pressure for gravel bikes

The tire pressure significantly affects the riding characteristics of your bike. Traction, steering behavior, susceptibility to punctures, efficiency, damping, etc., are all influenced by it.

The determination of the pressure is a mix of manufacturer specifications (see pressure on the tire sidewall), experience, riding style, terrain, rider weight, and more, which is why it's difficult to provide exact numbers here. The best approach is as follows:

Inflate your gravel tires according to the manufacturer's specifications.
Ride shorter test routes and adjust the pressure based on feel.
If you're undertaking longer tours, a mini pump with a pressure gauge is helpful. It helps you determine the exact tire pressure. You can experiment with different values and gradually find the perfect tire pressure.

If you're still missing the right gravel bike:

➽ Gravel Bikes at Bike Mailorder

all gravel bikes | Women's Gravel Bikes | Men's Gravel Bikes

You can find much more information in the other parts of our tire series:

Title image: Dimitrii Vaccinium on Unsplash

Gravel tires – what you should know!