MTB Frame materials - Carbon, Alloy, Titanium or Steel.

What’s inside this week:
1. Carbon, alloy or steel. The insider’s guide MTB frame materials.
2. Gadgets. This is what I do, so a weekly feature in TL.
3. Shorts - quick reads and Q&A’s.
4. Videos I’d send you if we were friends.

Carbon, alloy or steel. Choose the right frame for your next bike.

Metal, Magic, or Marketing? The Truth About MTB Frame Materials

Choosing a mountain bike frame material is like picking your ride-or-die trail buddy—it shapes your experience, your budget, and how many compliments you get at the trailhead. Alloy, carbon, steel, and titanium each have their own strengths, quirks, and price tags, but the question remains: which one is actually best?

Aluminum (or alloy, if you want to sound fancy) is the workhorse of the MTB world—light, stiff, and wallet-friendly. Carbon fiber is the performance-obsessed cousin, promising weight savings, stiffness, and the ability to make your bike look like it was sculpted by aliens. Steel brings old-school charm, a ride so smooth it feels like suspension, and a reputation for lasting longer than your riding career. And then there’s Titanium—the boutique dream material that’s lighter than steel, more compliant than alloy, and costs about the same as a used car.

But beyond the marketing hype and campfire debates, what really matters? Is carbon the ultimate choice for speed demons, or is alloy still the best bang for your buck? Can steel still compete, and is titanium really worth the premium? In this breakdown, we’ll dive into what each material offers, how they perform on the trail, and which one might be your perfect match. Because let’s be honest—half the fun of mountain biking is geeking out over the gear.

1. Carbon Fiber in MTB Frame Design: Hype or Holy Grail?

Carbon fiber has long been the darling of high-performance mountain bikes, promising featherweight builds, razor-sharp handling, and enough stiffness to make a pro racer swoon. It’s the material of choice for World Cup XC bikes, gravity machines, and boutique dream builds—but is it really the ultimate choice for everyone?

The Good: Why Carbon Wins Fans

Lightweight & Stiff: Carbon frames can be engineered to be incredibly light while maintaining stiffness, making them a go-to for riders chasing speed and efficiency. Less weight means faster climbs and easier bike handling.

Tuned Ride Feel: Unlike metals, carbon can be layered and shaped to control stiffness and compliance in different areas of the frame. This means engineers can fine-tune flex for comfort in one spot while maintaining rigidity elsewhere for power transfer.

Strong & Durable (When Built Right): Modern carbon frames are built to handle serious abuse, including big hits and crashes. Many brands now back their carbon frames with lifetime warranties, proving they have confidence in their durability.

Aesthetics & Aerodynamics: Carbon allows for sleeker, more sculpted frame designs, often with integrated cable routing, swooping lines, and wind-cheating profiles.

The Bad: Why Carbon Isn’t Always King

Pricey: High-quality carbon frames aren’t cheap. You’re paying for the material itself, the labor-intensive production process, and the prestige of riding the latest and greatest. Have a kidney to sell? I’m sure you’ll be fine without it.

Brittle Under Extreme Impact: While carbon is incredibly strong under normal riding conditions, catastrophic impacts (think rock strikes or major crashes) can lead to cracks rather than dents, which is often harder—and pricier—to repair.

Not All Carbon is Created Equal: Some brands use premium layups, while others cut corners. Cheap carbon frames can be heavy, fragile, or even poorly engineered, making them a worse choice than a well-made alloy frame.

Complex Repairs: While carbon can be repaired, it requires expertise and isn’t as straightforward as fixing a dented aluminum or steel frame.

2. Aluminum (Alloy) in MTB Frame Design: The Workhorse That Won’t Quit

Aluminum, or alloy as it’s often called in MTB circles, is the backbone of the modern mountain bike industry. It’s been the go-to material for decades, balancing affordability, durability, and performance. Whether you're on your first hardtail or a high-end enduro rig, chances are you've ridden an alloy frame at some point. But is it the best choice for your next bike? Let’s have a look.

The Good: Why Alloy Still Rules

Affordable & Widely Available: Alloy frames offer the best bang for your buck, making high-performance bikes accessible without requiring a second mortgage.

Strong & Reliable: Aluminum frames can take a beating. Unlike carbon, which can crack under extreme impact, alloy usually dents or bends, making damage more obvious and, in some cases, easier to ride with or repair.

Stiff & Responsive: Alloy frames are generally quite stiff, meaning they transfer power efficiently and provide a lively ride feel—great for sprinting, climbing, and aggressive handling.

Light Enough for Most Riders: While carbon is lighter, modern hydro-formed aluminum frames are impressively close in weight without the same price tag or fragility concerns. I did say ”for most riders “.

The Bad: Why Some Riders Look Beyond Alloy

Harsher Ride Feel: Alloy is stiff, which is great for power transfer but less ideal for comfort. Compared to carbon, steel, or titanium, it transmits more trail chatter into the rider, though good suspension or wide tires help.

Perceived weight: Even though alloy bikes have caught up to cheaper carbon frame weights - it is still considered by many to be heavier, and as you know, the mind is a powerful part of how your bike rides…

Fatigue Over Time: Unlike steel or titanium, aluminum has a finite fatigue life, meaning it will eventually weaken after years of hard use. That said, most riders will upgrade long before this becomes an issue.

Less Premium Appeal: Let’s be honest—while alloy bikes can look great, they don’t carry the prestige (perceived value) of carbon or titanium. If you care about trailhead flex (the kind that’s not suspension-related), alloy might not impress your riding buddies as much.

Verdict: Is Alloy Right for You?

If you’re looking for a solid, affordable, and dependable frame, alloy is hard to beat. It’s the choice of many budget-conscious riders, weekend warriors, and even some elite racers who prefer its mix of durability and performance. Unless you’re chasing grams or looking for the ultimate ride feel, an alloy frame will do the job—and do it well—for years to come.

3. Steel in MTB Frame Design: The Soul of the Ride

Steel is the original mountain bike material—a legend in the industry known for its smooth ride quality, durability, and timeless appeal. While it’s been somewhat overshadowed by alloy and carbon in the mainstream, steel still has a cult following among bikepackers, hardtail enthusiasts, Brits and riders who appreciate its classic feel. But is it the right choice for modern MTB?

The Good: Why Steel Still Has a Place on the Trails

Unmatched Ride Quality: Steel has natural compliance, meaning it absorbs vibrations and trail chatter better than alloy, giving you a smoother, more comfortable ride.

Super Strong & Durable: Steel is tough—really tough. It can handle years of abuse, and if it does take damage, it’s the easiest material to repair. It does rust, but that’s preventable.

Timeless Aesthetic & Feel: There’s a certain magic to steel bikes—the classic look, the smooth welds, and the knowledge that your bike could last a lifetime.

Great for Long Rides & Bikepacking: Because steel is naturally more forgiving, it’s a top choice for riders who spend long hours in the saddle, whether on back country trails or multi-day adventures.

The Bad: Why Steel Isn’t for Everyone

Heavier Than Other Materials: Steel frames are typically heavier than alloy or carbon. If you’re weight-conscious, steel might not be the best choice for a race bike. If you are a weight weenie - look elsewhere.

Can Rust If Not Properly Maintained: While modern coatings help, steel is still susceptible to rust if the paint or finish is damaged and moisture gets in.

Limited Availability in Full Suspension Bikes: Steel is mostly found in hardtails and custom-built bikes. If you’re after a lightweight, full-suspension machine, steel options are few and far between.

Verdict: Is Steel Right for You?

If you love comfort, durability, and the classic feel of a bike that "just rides right," steel is worth considering. It’s perfect for long-distance riders, bikepackers, and anyone who values ride quality over outright weight savings. It’s not for weight weenies or those chasing marginal gains—but if you appreciate craftsmanship and longevity, steel might just steal your heart.

4. Titanium in MTB Frame Design: The Dream Bike Material

Titanium—often called “Ti” in bike geek circles—is the holy grail of frame materials. It’s as strong as steel, as light as aluminum, and nearly indestructible. Throw in its rust-proof nature and the fact that it keeps its ride feel for a lifetime, and you have one of the most desirable (and expensive) frame materials on the planet. But does it justify the hype—and the price tag? I’ve been on a Titanium full suss for the last 3 years and absolutely love it. There’s actually one of my frames on the racks at William’s bike shop…ahem.

The Good: Why Titanium is the Ultimate Flex (Literally & Figuratively)

Light & Strong: Titanium offers the best of both worlds—lighter than steel but just as strong, making it ideal for riders who want durability without extra weight.

Incredible Ride Feel: Ti has a natural flex that smooths out bumps and vibrations, giving you a ride quality often described as magical. It’s stiff enough for power transfer but compliant enough to feel comfortable on long rides.

Lifetime Durability: Titanium doesn’t rust, fatigue, or degrade over time. A well-made Ti frame can literally last forever.

Premium Aesthetic: Brushed Ti frames look stunning, never need paint, and won’t chip or scratch like carbon or alloy. Plus, they have a certain prestige—owning a titanium bike is like having a Rolex for the trails.

The Bad: Why Titanium is a Luxury, Not a Necessity

Very Expensive: High-quality titanium frames cost a lot. You’re paying for the raw material, the skilled labor required to weld it, and the prestige of riding something special.

Not as Light as Carbon: While Ti is light, it’s not as light as carbon. If you’re a gram-counter racing XCO, carbon might still be the better choice.

Harder to Find in Full Suspension Designs: While some boutique brands make Ti full-suspension frames, they’re rare and often eye-wateringly expensive. Most Ti bikes are high-end hardtails or gravel rigs. This was a massive problem, so I designed my own bike, and made exactly what I wanted to ride.

Verdict: Is Titanium Right for You?

If you have the budget and want a bike that lasts a lifetime, titanium is unbeatable. It offers a dreamlike ride quality, stunning aesthetics, and durability that outlasts every other material. But for most riders, the price is hard to justify when alloy, steel, or carbon can do the job for much less.

Titanium isn’t about getting the best performance per dollar—it’s about owning something truly special. If you’re the kind of rider who keeps bikes for decades rather than chasing the latest trends, Ti might just be your ultimate forever bike.

5. Blended Frame Materials: The Best of Both Worlds?

Why choose just one material when you can have the benefits of two (or more)? Mixed-material frames are becoming more popular, with brands like Atherton Bikes pioneering carbon tube and alloy lug construction. These hybrid designs aim to combine the best characteristics of each material, offering strength, precision, and adaptability in a way that traditional frame-building methods can't always achieve.

Carbon Tubes + Alloy Lugs: A Perfect Match?

One of the most well-known examples of mixed-material MTB frames is Atherton Bikes, which uses carbon fiber tubes bonded to precision-machined aluminum lugs. This approach blends carbon’s lightweight stiffness with aluminum’s toughness and affordability, offering a unique set of advantages.

Custom Geometry Without Expensive Molds – Instead of manufacturing full carbon frames in rigid molds, brands like Atherton can CNC-machine lugs to fit different rider sizes and preferences, allowing for more customization.

Strength & Durability – Alloy lugs reinforce the most high-stress areas of the frame, reducing the risk of failure in places where carbon might typically be vulnerable (like head tube and bottom bracket junctions).

Repairability – Unlike full carbon frames, which are difficult and expensive to repair, modular construction allows for easier replacement of individual frame sections if damaged.

Ride Quality Tuning – Engineers can tweak stiffness and compliance by adjusting tube layups and lug dimensions, dialing in the frame’s ride feel for different riding styles.

Other Mixed-Material Approaches

While Atherton’s carbon-alloy method is gaining traction, other brands have experimented with different material blends:

Steel or Titanium Lugs + Carbon Tubes – Used in some custom-built gravel and road frames, this combo offers a mix of carbon’s light weight and the smooth ride feel of metal.

Carbon & Flax Composites – Some manufacturers integrate natural fibers like flax with carbon fiber to improve vibration damping while reducing environmental impact.

Aluminum & Carbon Blends – Some manufacturers use carbon seat stays or chainstays on alloy frames to add compliance and reduce weight without going full carbon.

The Downsides: Why Isn’t This More Common?

More Complex Manufacturing – While mixed-material designs offer benefits, they also require precise bonding and advanced engineering, which can drive up costs.

Weight Penalty vs. Full Carbon – While lighter than a full alloy frame, carbon-lugged designs aren’t always as feathery as a high-end full-carbon build.

Niche Market & Availability – Brands using this approach are still in the minority, meaning limited frame options and aftermarket support compared to traditional materials.

Verdict: Is a Hybrid Frame Right for You?

If you want the best of both worlds—carbon’s weight savings without the fragility, metal’s toughness without the weight penalty—a mixed-material frame is a brilliant option. Atherton Bikes and other brands leading this approach are proving that combining materials can enhance performance, increase durability, and even make frame production more sustainable.

For riders who want a tunable, repairable, and highly customized ride, mixed-material MTB frames might just be the future. 🚵‍♂️

6. Bamboo or wood for MTB Frame Materials: Nature Meets Engineering

Steel, aluminum, carbon, and titanium dominate the mountain bike world—but what about materials that break the mold? Wood, bamboo, and even composite hybrids are emerging as unique, sustainable alternatives to traditional frame materials. They may not be mainstream, but they offer a mix of ride quality, aesthetics, and eco-conscious appeal that turns heads at the trailhead. So, are they just a novelty, or do they have real-world trail potential?

Wood: The Artisanal Ride

Wooden bike frames might sound like something straight out of the 1800s, but modern wooden MTB frames are high-tech, handcrafted, and surprisingly capable. High-performance woods like ash, hickory, and even laminated hardwoods are used to create frames that absorb vibration like no other material.

Natural Shock Absorption – Wood has an organic damping quality, making for an incredibly smooth and comfortable ride.
Unique Aesthetics – No two wooden frames are exactly alike, and they have a craftsmanship vibe that’s hard to beat.
Sustainability – Responsibly sourced wood is a renewable resource, making it an eco-friendly choice.

Durability Concerns – While treated wood is tough, it’s not as impact-resistant as metals or carbon fiber.
Weight – Wooden frames tend to be heavier than carbon or titanium.
Moisture Sensitivity – Proper sealing is crucial to prevent warping or degradation over time.

Bamboo: Nature’s Carbon Fiber?

Bamboo bikes have gained traction in recent years, especially among eco-conscious riders. It may seem unusual, but bamboo's strength-to-weight ratio rivals that of aluminum, and it has natural vibration-damping properties that make for a smooth ride.

Surprisingly Strong & Flexible – Bamboo’s fibers are strong under tension, offering a ride feel similar to steel with added compliance.
Sustainable & Renewable – Bamboo grows quickly and requires minimal processing, making it one of the most environmentally friendly frame materials available.
Shock-Absorbing Ride – Natural flex and vibration damping make bamboo frames comfortable on rough trails.

Labor-Intensive to Build – Bamboo frames often require extensive handcrafting and joint reinforcement (often with carbon fiber or resin).
Durability & Longevity – While tough, bamboo can degrade over time if not properly treated and maintained.
Limited Full-Suspension Options – Most bamboo frames are hardtails, as the material isn’t ideal for complex suspension linkages.

Other Experimental Materials: Flax, Hemp, and Beyond

Some bike manufacturers are experimenting with flax fiber composites, hemp reinforcements, and even biodegradable resins to create frames with reduced environmental impact. These materials often blend with traditional ones (like carbon fiber or aluminum) to enhance strength while keeping weight and sustainability in check.

For riders who value craftsmanship over cutting-edge tech—or just want a bike that stands out—these materials might be the future. Or at the very least, the coolest ride at the trailhead. 🌿🚴‍♂️

With so very few of these made, I just did not go into details here. If you want to learn more on alternative bike materials, just let me know!

There’s no perfect frame material—only the right one for your needs, budget, and riding style. Whether you go for the affordability of alloy, the compliance of steel, the performance of carbon, or the prestige of titanium, the best bike is the one that makes you excited to ride.

Now, the real question is… which one speaks to you? 🚵‍♂️

Gadget of the week:

So my favorite of this week is the Ryder Groove Tool Plastic with chain breaker.

Nice compact, easy to slip into a pocket without the possibility of stabbing yourself in the leg, and all the tools you need for typical on-trail maintenance. Just this morning I was out on a demo bike, and had to set saddle height, saddle tilt and move the saddle on the rails next to road on a climb - never fun, but at least I had all tools on-hand, and enough leverage to crack all the bolts loose and tighten them up afterwards.

Q. What is a narrow/wide chainring?

A. A narrow/wide chainring is one-by system specific and designed with alternating narrow and wide teeth. The narrow teeth fit snugly between the inner chain links, while the wide teeth engage with the outer links. This design is super clever and reduces your chain from dropping off the chainring, especially on rough terrain. By securely holding the chain in place, you don’t need additional chain guides. The N/W chainring is half of the chain retention solution, the other half being a rear derailleur with a clutch.

About the author:
Hello, I’m Francoin, an Industrial Designer in the cycling industry based in Somerset West, South Africa.

Tools, lights, accessories and bicycle design is my daily graft.

This newsletter is to share some of the experience & industry insight that I pick up along the way, with fellow cyclists. If you are new to the sport, or been riding for many years, I plan to give you something of interest in every edition.

Thanks for subscribing and Happy trails!

FV

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