Why titanium is the best material for gravel bikes

By Lennard Zinn

Do you know someone who has broken a bike frame? Most likely it was made from carbon fiber or aluminum.

Over the past 10 years, big bike brands have have been pushing carbon fiber bikes on the world. Is this because the material is superior to all others or does it have more to do with profits? When asking executives at many large brands, the answer is increasingly clear. Carbon fiber bike frames have incredible profit margins. To be clear, I am not anti-carbon. I actually believe it has some great benefits. I just don’t believe it’s all it’s “cracked” up to be. I have ridden many carbon fiber bikes, and enjoyed them, but nothing beats the buttery smooth responsive ride quality of my titanium bikes.

Titanium Bike frames

Titanium is the Goldilocks of frame materials—not too stiff, not too flexible; not too heavy, not too light; not too brittle, not too ductile; not too springy, not too unyielding; not too lively, not too inert. It has the ideal balance of strength, weight, durability, and damping for a gravel bike.

Some great features of Titanium Bike Frames

• Stiff yet poppy for excellent power transfer
• Ultra compliant for a buttery smooth feel
• Lightweight
• Extremely durable
• Dent resistant
• Can never corrode

Power Transfer

Titanium has the stiffness to translate rider power into crisp, forward motion while having a lively response to pedaling and steering inputs and the forgiveness best appreciated on rough roads. It cannot corrode and needs no protective paint coating to get chipped by chunks of gravel thrown up by your and your riding companions’ tires. It has the strength and low density to be lightweight without tubes so thin as to be vulnerable to impact damage. Titanium frame tubes take enormous force to dent, bend or break, which, given the frequent knocking about and occasional crashes common in gravel riding, makes for a bike that will last you the rest of your life despite the abuse you may subject it to.

Strength to weight ratio

Titanium has the highest strength-to-density ratio of any metallic element. In the cold-drawn, seamless, 3Al/2.5V (3% aluminum, 2.5% vanadium, and 94% titanium) alloy our seamless frame tubes are made of, its strength is far higher yet—almost as high as that of chromoly steel, yet its low density (4.5g/cm³ vs. 8 g/cm³ for steel) ensures similar strength with close to half the weight. Aluminum’s density is 2.7g/cm³, 60% of titanium’s density, but since “3-2.5” titanium is around three times stronger than aluminum bike alloys, you only need a fraction of the amount of it.

Elongation

Possibly titanium’s most Goldilocks property is its high elongation coupled with high strength. Elongation is the measure, in percent, of how much a material can stretch or bend and still return to its original shape when the stress is removed (i.e., it is the change in length of a stretched material sample divided by its original length and multiplied by 100). You understand elongation intuitively, because you know better than to try to turn a screw with a fine kitchen knife made of high-strength, edge-maintaining steel; it’s so brittle it would snap off. You also know that the tip of an aluminum or carbon-fiber screwdriver would also break if you tried to unscrew a tight screw with one. Titanium is far more ductile than any of these materials; 3-2.5 titanium tubing has more than double the elongation of high-end steel bike tubing, over five times that of high-end aluminum bike tubing and nearly 10 times that of carbon fiber.

High elongation is why titanium frame tubes won’t dent when banged on a rock like aluminum or steel ones will or crack or delaminate like carbon-fiber ones will. In a heavy impact (think driving into a garage with the bike on the roof), titanium frames won’t crumple like steel frames or break like aluminum or carbon frames; their much higher elongation allows them to spring back, ready to ride. There simply is no longer-lasting bike-frame material.

The modulus of elasticity of a material is the amount of force it takes to flex it. Titanium’s modulus is about double that of aluminum and 60% of steel’s modulus. So, titanium allows the builder to make a stiff bike using tubes of similar wall thickness and only slightly larger in diameter than in a similarly-stiff steel bike; its low density makes it much lighter, and its high elongation makes the tubes super tough and hard to dent. Compared to a similarly-stiff aluminum bike, its tubes will be much smaller in diameter and much stronger and harder to dent.

Titanium’s springiness is obvious if you drop a titanium tube on a steel floor—it rings so brightly you cover your ears. The bright ring of a steel tube dropped on the floor points to steel’s well-deserved, legendary ride quality, but is not nearly as bright or loud as a dropped titanium tube, whose ride quality is even more legendary. A dropped aluminum tube makes a deader sound, and a carbon one deader yet.

Durability

Titanium will not rust like steel or corrode like aluminum; it’s why dental implants and artificial knees and shoulders are titanium. For a bike that will be ridden through mud puddles and water crossings and put away wet, what more could you want? Carbon shares this characteristic, but it lacks titanium’s resistance to damage in crashes and from rock strikes. The resin that binds a carbon bike together will also deteriorate with sun exposure over time creating weakness.

When compared to a carbon fiber frame, Titanium will not fail catastrophically if at all. When a carbon fiber frame gets dinged or scratched, a failure point has been created. This can lead to a catastrophic failure resulting in potential injury. Titanium just simply does not fail in this way, therefore it is one of the safest bike frame materials available.

If you want the ultimate material for a gravel bike, look no further than titanium. A titanium gravel bike is a lasting investment; you won’t ever have to replace it.