When you are looking to buy a new fork, one decision you’ll have to make is which material to go with. Two of the most common materials include steel and aluminum. Each fork material has its advantages and disadvantages. The ideal fork depends on the type of riding you do, where you ride, and your personal preference. In this guide, we’ll take a look at the pros and cons of riding a steel fork vs aluminum fork. We’ll cover compliance, weight, durability, cost, longevity, and much more. We’ll also talk about the best fork material for different types of bikes and riding. Whether you ride a road bike, a touring bike, or a gravel bike, hopefully, this guide helps you choose the ideal fork.
Steel Bike Forks
Steel is an alloy of iron with a small amount of carbon and traces of other elements which may include chromium, molybdenum, nickel, manganese, etc. The most common type of steel used for bicycle frame building is Chromoly steel. Lower-end forks may be made from high-tensile steel.
The fork arms, crown, dropouts, and steerer tube are all made from steel. Steel fork arms are welded, brazed, or lugged to the steerer tube. The steel tubes are often butted to reduce weight.
Some steel forks are stiffer than others. Manufacturers can vary the thickness of the fork arms and shape of the fork arms to increase or reduce fork flex.
Aluminum Bike Forks
Aluminum on its own is too soft for building bike forks. It’s alloyed with other elements such as silicon, magnesium, or zinc to increase strength and durability. The two most common aluminum alloys used for building bike forks are 6061 and 7005.
The fork arms, crown, dropouts, and steerer rube are made from aluminum. Aluminum forks can be hydroformed. This process uses high-pressure hydraulic fluid to shape the fork. The arms can also be butted to reduce weight. Aluminum forks are welded together.
Steel Vs Aluminum Fork
Steel and aluminum can both be used to build responsive and durable forks for a wide range of bikes. In this section, I’ll outline the differences and share some pros and cons of steel vs aluminum forks.
Compliance refers to the flex that occurs in the fork’s blades when you hit an obstacle such as a pothole or bump in the road. When you hit an obstacle, the fork blades flex a bit. They aren’t completely rigid. Some forks flex more than others. The amount of flex depends largely on the material that the fork is made of.
Vertical fork flex is desirable because it allows the fork to absorb some shocks and vibrations from the road. This improves comfort. If there is too much fork flex, handling and efficiency suffer. Ideally, the fork should have some vertical compliance as well as torsional rigidity.
Steel forks are more compliant than aluminum. When you hit a bump, steel forks flex slightly to smooth out the ride. When you use a steel fork, you’ll also feel less road buzz. Many riders find that the flex of steel forks gives the bike a lively ride feel. At the same time, steel forks don’t flex excessively. They offer a nice combination of compliance and rigidity.
Aluminum forks are much more rigid than steel. They don’t flex enough to absorb bumps or road noise. Bumps and vibrations are transmitted through the rigid aluminum fork to the handlebars. This can make for a harsher ride. You feel every bump more.
Aluminum forks need to be stiffer to maintain their strength. If aluminum fork arms were the same thickness as steel, they would be even more compliant. The problem is that they would flex excessively under load and fatigue and fail too quickly. Aluminum tubes need to be thicker to achieve sufficient strength.
The extra stiffness of aluminum forks does make the bike handle predictably and responsively. Particularly while riding at high speeds. This is because they do not twist or flex while cornering. This is important if you need precision. Aluminum is a good choice for road bikes for this reason.
The fork design also plays a role in stiffness. For example, a fork that is designed for disc brakes is stiffer than a fork that is designed for rim brakes. This is because the fork arms on disc brake bikes need to be stronger to resist torsional forces created by the disc brakes. Because the disc brake caliper is located on the side of the fork close to the axle, the fork wants to twist during braking. Stiff forks prevent this twisting. Disc brake bikes can have a harsher ride as a result.
Rim brakes, such as v-brakes, caliper brakes, and cantilever brakes, don’t create as much torque on the fork arms. The braking force is also applied at a stronger point on the fork, near the top center. The arms can be made thinner and more flexible without sacrificing strength or performance. Rim brake forks can offer a softer, more comfortable ride.
Winner: Steel forks offer a smoother ride because they are more compliant than aluminum.
Aluminum forks are lighter than steel forks. On average, a steel fork weighs 100-200 grams (3.5-7 ounces) more than a comparable aluminum fork. An average steel fork weighs around 800-1000 grams (28.2-35.3 ounces). An average aluminum fork weighs around 600-800 grams (21.1-28.2 ounces).
Aluminum forks are lighter because aluminum has a lower density than steel. The density of aluminum is about 2.7 g/cm^3 while the density of steel is about 8.05 g/cm^3. That’s about 1/3 of the density.
An aluminum fork isn’t 1/3 of the weight of a steel fork because aluminum isn’t as strong as steel. More material must be used to achieve the same strength. Even with the extra material, aluminum forks are still significantly lighter than steel. The lighter weight is the biggest advantage of aluminum forks.
There are several benefits to riding a lighter bike. First, acceleration is faster. You can spin up to speed more quickly when starting from a stop. A lighter bike is also more efficient. It takes less energy to maintain your speed or climb hills. A lighter fork can be an excellent choice for cyclists who are looking to improve their performance.
The weight difference between a steel and aluminum fork is insignificant for casual cyclists. For a competitive cyclist, the weight advantage can be crucial. If you’re looking to save more weight, consider a carbon fiber fork.
Winner: Aluminum forks are lighter than steel forks.
Steel forks are more repairable than aluminum. If a steel fork gets bent during an accident, it can usually be bent back into shape. Bending a steel fork slightly doesn’t weaken it. Even if a steel fork gets severely damaged, a professional frame builder can usually make it rideable again by bending it back into shape and welding or brazing some additional material on for reinforcement. In many cases, cracked steel can also be repaired. It may not look pretty but it will be safe to ride.
In most cases, aluminum forks can’t be repaired. If you spot a crack caused by fatigue, there is no way of knowing when another crack will form. If an aluminum fork gets bent in an accident, there is no way to determine if the structural integrity of the fork has been compromised. It’s not safe to simply bend aluminum back into shape. Bending the material can weaken it further.
Steel is also an easier material to work with than aluminum. No advanced welding tools or skills are required. Pretty much anyone who knows how to weld can weld steel. This makes steel a good choice for bicycle tourists and bikepackers who plan to ride through remote regions or the developing world. Wherever you are, you can always find a welder who can work with steel. There is always a backyard welder around. You won’t be left stranded with a damaged fork. Most touring bikes come with steel forks.
Aluminum is also a more difficult material to work with. If your aluminum fork cracks and you want to attempt a repair, you’ll have to find someone with the proper tools and knowledge to weld aluminum. Aluminum is more difficult to weld because it needs to be tempered or heat-treated in order for the weld to hold. Most professional frame builders won’t touch a damaged aluminum fork for liability reasons. They will simply recommend you replace it. The cost of repair is also higher. It’s usually cheaper to simply replace an aluminum fork rather than repair it.
Winner: Steel forks are more repairable and easier to repair. Aluminum forks usually can’t be repaired.
Steel forks can rust. This is because steel is more reactive than aluminum. Steel is more likely to corrode when exposed to oxygen, moisture, and salt, which are common in the air and on roadways. As rust builds up, it weakens the metal. Eventually, a rusted steel fork becomes unsafe to ride. It can eventually fail.
Aluminum can also corrode but it is much more corrosion-resistant than steel. When aluminum corrodes, it forms aluminum oxide. This material is much stronger than rust. It creates a protective layer over the metal that protects it from further corrosion. This prevents your aluminum fork from corroding away over time.
It’s important to inspect your fork for signs of rust and corrosion on a regular basis. Once rust or corrosion has set in, it’s impossible to completely reverse the damage. If you do find rust on your fork, remove it and apply some paint or clear coat over the spot to prevent further rusting. Check out this guide for some tips on removing rust.
You can also take preventative measures to protect your steel bike fork from rust. One way to do this is to apply a rust inhibitor. This will create a barrier between the steel and the elements, helping to prevent rust and corrosion from taking hold. You can also prevent corrosion by regularly cleaning your bike.
If you store your bike indoors and make sure it’s clean and dry before putting it away, you shouldn’t have any issues with rust. Steel forks can last decades if it’s taken care of. For most riders, rust isn’t an issue. It’s extremely rare for a fork to rust beyond repair.
If you only ride by the sea, during the winter on salted roads, or in extremely wet areas, you might be better off with an aluminum fork. You won’t have to worry about corrosion as much.
Winner: Aluminum forks are far less likely to corrode than steel.
Steel and Aluminum Fatigue Limit
The fatigue limit is the stress level below which a material can withstand an infinite number of fatigue cycles without failing. Steel has a high fatigue limit. Aluminum does not have a real fatigue limit.
This difference is especially important in applications where repeated stress is applied, such as in bike forks. A bike fork experiences hundreds or even thousands of stress cycles every time you go for a ride. If it’s made of steel, it can handle those stress cycles without issue. But if it’s made of aluminum, there’s a much higher chance that it will eventually break.
In theory, steel can withstand stress below its fatigue limit an infinite number of times without failing. A steel fork could last almost indefinitely if it’s never pushed beyond the fatigue limit. If stress is applied above the fatigue limit, the material will start to deform and eventually fail.
Every time you apply a load to an aluminum fork, it fatigues. Small stress cycles that wouldn’t affect a steel fork fatigue aluminum. This stress adds up over time until the fork fails. A well-made aluminum fork can withstand millions of fatigue cycles. Eventually, it will fail. Most aluminum forks will last for decades with regular use. Fatigue usually isn’t an issue for the average cyclist.
Of course, no fork will last forever. That’s why it’s important to inspect your fork for fatigue once in a while. More on that in the next section.
Winner: Steel frames don’t fatigue and fail as quickly as aluminum because steel has a high fatigue limit. Aluminum doesn’t have a fatigue limit
Fork Failure and Safety
Steel forks can be safer to ride than aluminum. The reason is that steel is less likely to suddenly fail. In most cases, steel will give you some early warning signs when it reaches the end of its life before it fails completely. An aluminum fork may not give you the same warning.
Steel and aluminum forks fail in different ways. Steel forks will usually crack first, then slowly fail. During this time, the ride quality of the bike may change. Maybe the steering feels different. You may hear some creaking. Steel forks could also bend or dent during a hard impact. Steel forks with a slight bend is still safe to ride, as long as it isn’t cracked. A cracked fork isn’t safe. Cracked steel usually doesn’t fail suddenly. It bends first.
Sometimes it isn’t obvious when an aluminum fork is damaged and about to fail. You could miss a hairline crack during an inspection. There could be damage in the steerer tube that you can’t see without removing the fork. Poor quality materials or manufacturing defects can also make aluminum forks unsafe.
If an aluminum fork bends or dents during an accident, it’s not safe to ride. It is difficult to determine the structural integrity of a damaged aluminum tube. It may be safe to ride but it’s not worth risking it.
In rare cases, aluminum forks can fail catastrophically and without warning. If this happened while you were riding at speed, you could be seriously injured or killed. Imagine bombing down a hill at 30 mph when your fork fails and sends you into the ground headfirst.
This type of failure isn’t common but it has been documented. For example, this article tells the story of a rider who died of severe head and neck injuries after an alloy steerer tube failed. It is unknown whether the steerer tube failed due to fatigue or due to a flaw in manufacturing.
Regardless of the material of your fork, you should thoroughly inspect it for damage at least once per riding season and after a crash. Aluminum forks need to be inspected more frequently than steel forks.
To inspect your, look for cracks, dents, or crimping in the arms and fork crown. Inspect the dropouts to make sure they aren’t cracked or worn. Also, check to make sure the front wheel is aligned. The bike should ride straight when you hold the handlebars straight. Listen for creaks as you ride. Pay attention to changes in ride quality. If you spot any damage, you should take the bike to a professional for a safety inspection. It may be unsafe to ride. If your fork is damaged, you’ll need to repair or replace it.
Winner: Steel forks may be safer to ride than aluminum.
Steel and aluminum forks cost around the same. On average, a rigid steel aluminum fork costs around $90-$150. You can buy an entry-level fork for around $60. High-end forks cost $300+.
Suspension forks are significantly more expensive due to the added complexity. Most suspension forks cost around $200-$600.
Winner: The price of steel and aluminum forks is similar.
Steel forks are more durable than aluminum. They can take a beating. Steel can be scratched deeply, dented, and even bent without losing its structural integrity.
Steel can also handle a far harder sudden impact than aluminum. This is because steel is a less brittle material. It usually doesn’t crack during an impact. Instead, it bends. You can ride a steel fork that is damaged, as long as it’s not cracked or severely bent.
For these reasons, steel forks are ideal for commuters and bicycle tourists, who need a strong and durable bike. Steel won’t leave you stranded. Steel forks are also ideal for those who ride in cycling disciplines where accidents are common, such as downhill mountain biking. They can handle years of abuse.
Aluminum isn’t quite as tough as steel. During a hard impact, it can crack and fail. Aluminum usually doesn’t bend. It is a much more brittle material. Aluminum can also fail from fatigue more quickly than steel.
Both steel and aluminum forks are resistant to everyday wear and tear such as abrasions. A small scratch is usually just cosmetic. They can also both hold up to minor accidents. If you fall off your bike at low speeds or drop your bike, the fork will be fine.
Winner: Steel forks are more durable than aluminum.
Performance: Speed and Handling
Aluminum forks are generally considered to be the better choice for performance-oriented riders. That’s because aluminum forks are lighter and stiffer than steel forks.
The lighter weight allows you to accelerate faster and maintain a higher average speed. The rigidity allows you to corner harder without the fork flexing. This gives the bike more precise and responsive handling.
Steel forks, on the other hand, are typically heavier and less rigid. Performance suffers as a result. The extra weight makes the bike slower to accelerate. It takes more energy to maintain your speed. Steel forks can flex and twist slightly while cornering. This can make the bike handle a bit less responsively.
Winner: Aluminum forks offer better performance than steel forks.
Aesthetics are an important factor to consider when choosing between a steel or aluminum bike fork. You want your fork to match the look of the rest of your bike.
Steel forks have a more classic look. The tubes are round. Steel fork tubes are also smaller in diameter than aluminum. This is because steel is stronger. Less material is needed to make the fork arms sufficiently strong. The round and skinny steel tubes can look out of place on an aluminum frame with oversized aluminum frame tubes.
Aluminum forks have a more modern look. The tubes usually aren’t round. They often feature a bladed or teardrop shape. This design improves aerodynamics. This can make the bike look a bit sleeker and faster. Installing a modern aluminum fork on a bike with a classic steel frame may look out of place.
Winner: Looks are subjective. Personally, I prefer the looks of classic steel forks. Try to choose a fork that matches the look of your bike’s frame.
Longevity: Fatigue and Degradation
Steel forks generally outlast aluminum forks. The main reason is that steel doesn’t fatigue if it’s not overstressed. In theory, a steel fork could last indefinitely if it’s taken care of. People are still riding steel forks that are 50+ years old. I ride a Schwinn High Sierra mountain bike from the 80s. Many components have been replaced but the frame still rides like it’s new.
Aluminum doesn’t last as long as steel. This is because aluminum fatigues more quickly. Every time you apply a load to your aluminum fork, it fatigues. This adds up over time until the fork fails. How long aluminum forks will last, depends on how many fatigue cycles it goes through. A quality aluminum fork should easily last 20 years if it’s taken care of. It may last much longer. If you ride your bike daily, you may only get 10 years out of an aluminum fork.
Winner: Steel forks last longer than aluminum forks.
You can change the hub spacing on steel forks. If you want to install a slightly wider or more narrow rear hub in your fork, you can bend the fork arms slightly to make it fit. This process is called ‘cold setting’.
You can pretty easily move the fork arms 5-10mm in either direction without compromising the fork. This allows you to use a wider range of hubs when the time comes to upgrade or replace your wheels.
Some older bikes have 91mm or 96mm front hub spacing. Most modern bikes use 100mm hubs. You can carefully spread an old fork to fit a modern hub. For more info, check out this guide.
Because aluminum is so rigid, you can’t bend the fork arms without risking causing damage. You could weaken or crack the metal if you bend them too far. This means you can’t adjust your front hub spacing like you can with steel forks. This limits your front hub options when replacing or upgrading your wheels.
Winner: The hub spacing on steel forks is adjustable.
Steel forks are more common than aluminum. If you’re looking for a new fork for your bike, you’ll have far more options to choose from if you go with a steel model.
If you want a lightweight high-performance fork, carbon fiber models are the standard these days. Aluminum forks are less common. They are far less popular than steel or carbon forks. You’ll have fewer options to choose from if you want to buy aluminum forks.
Winner: More steel fork options are available.
Both steel and aluminum forks require some maintenance. Steel forks need to be cleaned and dried when they get wet so they don’t rust. You might also need to treat the fork with a rust inhibitor and paint over scratches to prevent rust from forming.
Aluminum forks need to be inspected periodically for cracks. Fatigue cracks can appear suddenly and make a fork dangerous to ride. You need to inspect aluminum more frequently than steel.
Winner: Both require minimal maintenance.
Tire Width and Fork Material
A rigid fork only provides a small amount of bump and vibration absorption. The tires play a much larger role in comfort. A rigid fork cannot match the cushioning of a set of wide tires operating at low air pressure. A bike with an extremely rigid aluminum fork and wide tires will offer a smoother ride than a bike with a compliant steel fork and narrow tires run at high air pressure.
If you’re looking for a more comfortable ride, you’re better off choosing a fork with wide tire clearance. This allows you to run wider tires at lower PSI. Softer tires can deform around obstacles and absorb bumps and vibrations. With wider tires, you’ll get the benefit of a smooth ride without having to worry about fork stiffness. You can choose whichever fork material you prefer.
Keep in mind that if you do choose to run wide tires, you’ll need to get a wheelset that can accommodate them. Many modern road bikes come with wider rims these days, so this shouldn’t be a problem.
Your brake type can also limit your tire clearance. V-brakes and cantilever brakes offer good clearance. Caliper brakes can be limiting if you want to run extra wide tires. Disc brakes don’t affect tire clearance but do require a stiffer fork to prevent lateral flex.
Can I Ride an Aluminum Frame With a Steel Fork?
Yes. Steel forks are compatible with aluminum frames, and the two materials can actually complement each other quite well.
Steel forks tend to be softer, which can absorb bumps and vibrations better than aluminum. Aluminum frames are far lighter than steel. This pairing can create a bike that is both comfortable and efficient. If you’re looking to build or upgrade a bike, don’t be afraid to mix and match steel and aluminum components.
Can I Ride a Steel Frame with an Aluminum Fork?
A steel frame and an aluminum fork is not a common combination. Steel framed bikes are known for their smooth ride quality. If you install a stiff aluminum frame, the ride can feel harsh. Steel framed bikes are also significantly heavier than aluminum framed bikes.
That said, there is nothing wrong with running a steel frame with an aluminum fork. If you have a steel frame that you love and want to install an aluminum fork on it, you can. You just need to make sure the fork fits the frame.
Another Option: Carbon Fiber Fork
Carbon forks are another popular option. Carbon forks are typically lighter than aluminum forks. They can also offer superior stiffness to aluminum forks. Most professional cyclists ride carbon forks for this reason.
However, carbon fiber forks are also generally more expensive than other types of forks. As a result, they are often reserved for high-end road and mountain bikes. Carbon forks are also less durable than steel and aluminum models. Carbon forks are somewhat brittle. They can crack during an impact. Whether you’re looking for a lightweight racing fork or a durable option for off-road riding, a carbon fiber fork may be the right choice for you.
For more info, check out my guide to carbon vs steel forks.
What About Suspension Forks?
If you plan to spend most of your time riding off-road or on rough gravel roads, you might consider installing a suspension fork on your bike. There are two main types of suspension forks for bicycles: coil and air.
Coil suspension forks use a metal spring to provide resistance while air suspension forks use air pressure. Each type has its own advantages and disadvantages. Coil suspension forks are generally more expensive than air forks, but they tend to be more durable and require less maintenance. Air suspension forks, on the other hand, are lighter-weight and easier to adjust.
Suspension forks are usually made from a combination of steel and aluminum components. For example, the stanchions and fork body are usually made from aluminum due to the lighter weight. The coils on coil forks are usually made from steel.
When choosing a suspension fork, you’ll want to consider how much suspension travel you’ll need, rider weight, sensitivity, fork weight, adjustability, and more. For more info, check out my guide to air vs coil suspension forks.
Who Should Use a Steel Fork?
Steel forks can offer many advantages to riders. Firstly, steel is a very compliant material, meaning that it can absorb bumps and vibrations from the road surface. This can lead to a more comfortable ride, This is ideal for those who ride on rough roads and those who spend a lot of time in the saddle. For example, gravel riders can greatly benefit from steel forks.
Secondly, steel is a very durable material, meaning that it is less likely to be damaged than other materials such as aluminum or carbon fiber. This is particularly important for those who ride in remote areas, where it may be difficult to find a bike shop that can carry out repairs. Bicycle tourists and bikepackers can benefit from the durability of steel forks.
Finally, steel is a very long-lasting material. A bike with a steel fork is likely to last for many years without the need for much maintenance. For this reason, steel forks are an excellent choice for those who want to ride the same bike every day for years on end, such as commuters.
Who Should Use an Aluminum Fork?
There are a few different factors to consider when deciding whether or not to use an aluminum fork on your bike. One is the weight of the bike. If you’re looking for a lighter bike, aluminum is a good choice. An aluminum fork isn’t as light as a carbon fork but much cheaper.
Aluminum is also a good choice for those who want better performance out of their bike. Aluminum forks are known for being stiff, so they transfer energy efficiently. They corner quickly and predictably. This makes aluminum a good choice for competitive cyclists and those who value performance. If you’re in the market for a road bike, you might consider aluminum.
Another factor to consider is corrosion. If you live in a wet or humid climate, aluminum is less likely to corrode than steel. It’s also less likely to be damaged by salt water if you ride near the ocean.
All things considered, aluminum is a good choice for those who want a light, high-performance bike that will hold up in tough conditions. Aluminum forks hold up better than carbon fiber.
What is the Best Material for a Bike Fork?
When it comes to choosing the best material for a fork, there are three main contenders: steel, carbon fiber, and aluminum. Each material has its own advantages and disadvantages, and the best choice for each rider will depend on their individual needs.
Steel is the heaviest of the three materials, but it is also the most durable. Carbon fiber is significantly lighter than steel, making it the best choice for performance-oriented riders. However, it is also more fragile and less forgiving than steel. Aluminum is kind of a middle ground between steel and carbon fiber. It’s heavier than carbon fiber but lighter than steel. It’s more durable than carbon fiber but less durable than steel.
Ultimately, the best material for a fork depends on the type of riding you do, where you ride, and personal preference.
Final Thoughts About Steel Vs Aluminum Forks
If you’re looking for a bike fork, steel and aluminum are both great materials. The best fork material depends on a number of factors including the type of riding you do, where you ride, and personal preference.
If you value comfort and durability, steel is the best choice. If weight and performance are more important to you, aluminum is the better option. Whichever fork material you choose, hopefully, this guide has helped you in making your decision.
Does your bike have a steel or aluminum fork? Share your experience in the comments below!
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