Titanium Grades Explained: Choosing the Right Tubing for Your Bike

beautifully tig welded bottom brakcet

Titanium has long been revered in the world of custom bike building for its unmatched blend of strength, weight, durability, and exceptional ride quality. But not all titanium is created equal.

If you’re considering investing in a titanium bike frame, it’s worth understanding the different grades of titanium tubing used in the cycling industry—because it directly affects performance, comfort, and longevity.

At Enigma Bicycle Works, we’ve specialised in titanium craftsmanship for nearly two decades. In this guide, we’ll break down the most commonly used grades, explain their differences, and highlight where they’re used in our own range of custom titanium bikes.

What Is a Titanium Grade?

Titanium is categorised into different "grades" based on its alloy composition and mechanical properties, as defined by ASTM (American Society for Testing and Materials). The most commonly used titanium grades in bicycle framebuilding are:

  • Grade 9 (3Al/2.5V)
  • Grade 5 (6Al/4V)
  • Grade 2 (CP2 - Commercially Pure)

Each offers distinct characteristics that influence ride feel, frame weight, and how the bike handles.

Grade 9 Titanium – 3Al/2.5V: The Industry Favourite

Composition: 3% Aluminium, 2.5% Vanadium, 94.5% Titanium
Properties: Medium strength, excellent weldability, fatigue-resistant
Common Uses: Main triangle tubes, chainstays, seatstays

Often called the workhorse of titanium bike building, Grade 9 (3Al/2.5V) is the most commonly used alloy in the cycling industry. It offers the ideal balance of stiffness, compliance, and workability, making it the go-to choice for most performance titanium frames.

At Enigma, we use Grade 9 titanium extensively across our core models like the Escape, Etape, and Echelon. These bikes are designed to combine long-distance comfort with responsive handling and long-term durability—exactly what Grade 9 delivers.

In addition to our proprietary Grade 9 tubing, we also build with Reynolds 3Al/2.5V titanium on selected models such as the Eikon and Esker. Reynolds tubing is known for its slightly thinner wall profiles and is marginally lighter, offering subtle weight savings and a smoother ride feel—particularly well suited to gravel and road builds where precision and compliance matter.

Grade 9 Titanium Tube

Grade 5 Titanium – 6Al/4V: The Elite Performance Alloy

Composition: 6% Aluminium, 4% Vanadium, 90% Titanium
Properties: High strength, less ductile, more difficult to form
Common Uses: Bottom bracket shells, head tubes, dropouts, premium performance frames

Grade 5 (6Al/4V) titanium offers roughly 50% more tensile strength than Grade 9. That makes it perfect for high-performance applications, particularly where stiffness and efficiency under load are critical. However, it's harder to work with and requires more advanced tooling and skill to fabricate.

At Enigma, we exclusively use Grade 5 (6Al/4V) titanium on our flagship model, the Excel. Its Grade 5 main triangle maximises power transfer and responsiveness, delivering an uncompromising ride for serious riders.

Grade 5, 6al 4v Titanium Tubing

Grade 2 Titanium – Commercially Pure: Simple but Limited

Composition: ~99.2% pure titanium
Properties:  Very ductile, corrosion-resistant, lower strength
Common Uses: Budget frames, accessories, small components

Grade 2 titanium (also called CP2) is a commercially pure variant known for its corrosion resistance and softness. It’s easy to form and weld but lacks the mechanical strength of Grade 9 or Grade 5. That makes it less suitable for structural frame components. For this reason, it's rarely used in high-end performance bicycles but might be found in entry-level frames or certain components like bolts, trumpets (as shown below) or bottle cages.

Summary Table: Comparing Titanium Grades for Bikes

Titanium Grade Composition Strength Weldability Common Use
Grade 2 Pure Titanium Low Excellent Budget frames, accessories, bolts
Grade 9 3Al/2.5V Medium Excellent Main tubes, stays (industry fav)
Grade 5 6Al/4V Very High More difficult Dropouts, BB shells, elite frames

Why Titanium Grade Matters for Your Ride

Choosing the right titanium grade can transform the way your bike feels and performs. Grade 9 provides the all-day comfort and reliability ideal for most riders, while Grade 5 pushes the limits of weight savings and stiffness for those chasing marginal gains.

At Enigma, we tailor every model to match the material’s strengths—whether that’s a responsive all-road machine or a fully bespoke custom build. Understanding these titanium differences gives you the insight to choose the right frame for your riding style and goals.

Final Thoughts: Why Expertise Matters in Titanium Framebuilding

Working with titanium isn't easy—it takes experience, specialist tools, and a deep understanding of the material. At Enigma, we've been crafting British-made titanium frames for nearly 20 years, with every weld, tube, and fit-out reflecting our commitment to quality and performance.

Whether you’re exploring your first titanium bike or looking for your next dream custom build, we’re here to guide you.

👉 Explore our full range of titanium bikes
📞 Get in touch with our team to talk through your build