Which is better? Gravel bike frame material types and features

Types of Gravel Road Frame Materials

There are four main types of gravel road frame materials

1. aluminum
2. carbon
3. chrome-mobliden
4. titanium

Aluminum

Aluminum frames are often used in gravel road bikes. Aluminum is used to make beer cans, for example.

Aluminum is relatively soft and easy to process among metals, and is often used not only for gravel road bikes, but also for MTB and cross bikes. Because it is metal, it is resistant to impact from blows such as falling off a bike, but it is not very resistant to shape changes, and its frame rigidity is low.

The good thing about aluminum-framed gravel roads is that they are easy to handle, even for beginners. Since it is a light metal, it can be customized to make a lightweight gravel road, and you don’t have to worry too much about falling off the bike or wheeling it around.

As for weight and stiffness, it cannot compete with carbon, the current mainstream road bike frame material, but it is a “can’t-miss” frame.

Carbon

Carbon is currently the mainstream road bike material. Most of the higher grade road bikes are carbon frames, and carbon frames are also increasingly being used in gravel road bikes and MTBs for riding on rough roads.

Unlike metal, carbon frames are formed by solidifying carbon sheets with epoxy or other resins to form the frame, which allows for a high degree of freedom of shape, making it possible to create special (non-pole-shaped) and aero shapes.

On the other hand, carbon fiber itself is a very strong material, but the resin that solidifies the carbon fiber is very vulnerable to a single point of impact, and there is a risk of cracking even without a major impact such as falling off the bike.

However, when riding on gravel, it is surprisingly easy to fall off the bike, and if there is a rock or tree at the end of the fall, the frame may be damaged to the point of total replacement in the worst case scenario.

Because of these “difficult to handle” characteristics, carbon gravel road bikes are mostly high-end lines for advanced riders, while entry to middle grade are mostly aluminum.

Chrome-mobliden

In the bicycle community, a frame made of chrome-mobliden steel is called a “chromoly frame” for short. Compared to aluminum, chromoly is a less rigid material with a unique springiness that makes for a softer ride.

The disadvantage, however, is that there is less flexibility in the shape of the frame because the pipes are welded together. It is also the heaviest of the materials selected for this report.

However, the classical appearance of chromoly is cool, and in the past few years, the number of users who choose chromoly gravel bikes has been increasing.

Although there are few types of chromoly gravel bikes available from major manufacturers, you can order your own chromoly frame customized to your own taste from a frame builder.

Titanium

Titanium is a light and hard metal. It is a “super high-end material” for road bikes, and a titanium frame road bike is a symbol of one of the high-end models.

It is easy to process like aluminum, but still has stiffness and light weight similar to carbon, so it is chosen by users who are afraid of carbon but want to save weight, but the price of the frame alone is more than $3,000.

Like chrome mobliden, there are few types of gravel road bikes with titanium frames, but some frame builders carry titanium, so you can order a frame to your liking.

Which material is stronger?

As an aside, let’s also look at the strength of the material itself.

In the Youtube video below, the same size material is subjected to a bending load to see how much difference in strength there is.

HYDRAULIC PRESS VS TITANIUM AND CARBON FIBER, BENDING TEST | Youtube

Carbon is 20% stiffer than aluminum, and titanium, by far the hardest material, withstands more than three times the pressure of carbon.

The best material for a gravel road bike is chosen based not only on the strength of the material, but also on the total weight, ease of manufacture, and cost. The strength of the material itself is also a good guide when selecting a material, although it is only for reference as it varies depending on the structure and thickness of the frame, even with the same material.

Compare gravel road bike frame materials! Which material is better?

Let’s compare the features of each frame material we have looked at so far.

Material	Stiffness	Price	Weight	Handling
Aluminum	△	◎	○	◎
Carbon	◎	△	◎	△
Cr-Mobliden	△	△	△	◎
Titanium	◎	△	◎	◎

For gravel bikes, where the risk of falling or crashing on rough roads is higher than on road bikes, titanium frames are best, except for price. It is the same reason why many high-end MTBs have titanium frames.

However, the disadvantages of titanium are that it is too expensive and the frame shape cannot be the trendy aero shape. This is probably why carbon frames are becoming more and more common in gravel bikes.

Aluminum is the best balanced choice. Aluminum is currently the best choice because it is inexpensive, the frame shape is relatively flexible, and even beginners can enjoy gravel riding casually without worrying about cracks from falling off.

Beginners should not hesitate to choose an aluminum frame.

Carbon gravel bike users are often heard to say, "I fell off the bike on a forest road or trail and damaged the frame. Even if you have some experience, the probability of falling off the bike is higher than on paved roads, so it is not suitable for beginners.

On the other hand, expensive titanium frames are too expensive for beginners, and chrome mobliden frames are too heavy and soft, making them somewhat habitual for beginners.

Aluminum is the best choice.

This is the reason why most of the entry to middle grade gravel bikes are aluminum frames.

Carbon frames are also available if you only ride on gravel roads.

On the other hand, if you are a light gravel user who says “gravel is just a little gravel road, but mostly paved road,” carbon frame is also available.

The only disadvantages of carbon frames are price and weak impact to a single point, so if your budget allows, you may want to buy a carbon frame gravel bike from the beginning to enjoy a crisp ride.

If you want a classic look anyway, chrome mobliden.

Regardless of stiffness or weight, if you want a “classic silver bike!” If you want a classic silver bike regardless of stiffness, weight, etc., you can choose a chrome molybdenum bike.

Most gravel bikes come in subdued colors such as black or moss green, and the frame shape is moderately aero and in vogue.

With chrome mobliden, you can build a classic gravel bike with a pipe feel.