Titanium tube bike frames are made for high-end bicycles produced by top manufacturers in the industry. The reason for choosing titanium lies in this material’s strength and other unique properties, including its rather reduced weight (compared to other materials commonly chosen for bike frame tubes).
Titanium – A Reliable Choice for Bike Frame Tubes
Even though you might expect for titanium to be not so commonly found, the truth is that this is one of the most encountered metallic elements out there. It is appreciated for its properties, being often chosen for the making of bike frame tubes. One of its most essential properties is the density. Titanium’s density is double the one of aluminum but, compared to steel, it is less dense (the percentage is almost half).
Another interesting property is the one related to stiffness. Explained in scientific terms, this is known as modulus. It basically explains the relationship between stiffness and flexibility. The titanium that is chosen for the making of bike frame tubes has a modulus of 15 million pounds/sq. inch. This is 50% less than the modulus of steel, hence an advantage for using titanium. Frame stiffness is often delivered by choosing a material that can be modified to the expected ratio; with titanium, a high level of execution is necessary, to guarantee a flexible ride, without affecting the resistance of the frame.
Manufacturers are choosing titanium because of its properties. It delivers better strength than other materials, it has a low density compared to the one of steel and the modulus is alright, once again compared to the one of steel. These properties allow manufacturers to deliver bike frame tubes that are resilient and capable of absorbing the shocks that normally appear during a ride. The one thing one has to understand is that titanium cannot be used for the making of super lightweight bike frame tubes. If that were to happen, the frame would be too flexible and it would suffer modifications under cycling pressure.
In choosing a particular material for the making of bike frame tubes, manufacturers are taking into consideration several factors, including the one of safety. Titanium is a safe choice, as it has a high elongation percentage to deliver, meaning between 20-30%. First of all, you should know that elongation refers to the ability of a material to curve before suffering modifications. Compared to titanium, steel has an elongation of 10-15%, while aluminum delivers between 6-12%. Titanium is also a great choice, as it has a high endurance limit. This property is also known as fatigue strength, making a reference to how durable the bike frame tubes are when subjected to physical stress. This can refer to either part of the cycling process, including pedaling or even bumps that might appear during the ride.
Advantages and disadvantages of titanium tube bike frames
These are actually reflected by the pros and cons of using titanium as a material for the making of the tubes.
The pros of using titanium are:
- High resistance and strength
- Moderate density – higher than aluminium, lower than steel
- Moderate stiffness
- Ability to absorb shocks
- Superior resistance to corrosion.
The cons of using titanium are:
- Price – titanium is expensive (extraction and processing costs)
- Manufacturing – welding/shaping difficulties (aerodynamic shapes – increased difficulty)
- Modulus – does not modify, despite one choosing a superior level of strength for the actual material
- Repair process is complicated
- Weight – there are other materials out there which have a lighter weight.
Titanium is advantageous to be used for bike frame tubes because of the strength-to-weight proportion and also because of the reduced corrosion potential. As for the disadvantages, these lie in the price and fabrication.
For the making of bike frame tubes, manufacturers use titanium alloys. These have been initially used in the aerospace industry, but nowadays have been successfully integrated into other industries as well. The titanium grades actually represent the combinations of alloys used. Grade 9 is represented by an alloy containing 3.5% aluminum and 2.5% vanadium. Grade 5 contains 6% aluminum and 4% vanadium. It should be mentioned that manufacturers have tried to experimentally use pure titanium for the making of bike frame tubes. The tubes that resulted from the process did not have the desired level of durability, necessary for an active riding experience.
Grade 9 is often used to make these tubes, as it delivers the expected level of durability and it also has a wide range of mechanical advantages. On the other hand, grade 5 is more commonly used for parts such as bottom brackets, frame dropouts or brazed-on accessories. It is appreciated for the enhanced strength it has to offer. As for the making of tubes, it can be used as well. What one needs to understand is that grade 5 comes in a sheet form (seamless does not currently exist), being welded into tubes. The result is a tube that presents a high chance of cracking and failure. Also, there are two other grades of titanium, meaning 11 and 2. These are not used for the making of bike frame tubes, but rather in other industries. Plus, their mechanical features are of inferior quality.
Alternatives to titanium and comparison
The choices for bike tube frame materials are diverse nowadays, including steel, aluminum (most often as alloy) and carbon fiber. New materials are always added to the list, each having its own set of advantages. Among these materials, you will find thermoplastic composites, appreciated for their impact resistance. Other materials include magnesium (density – half of the one of aluminum, elongation 10-11%), scandium and beryllium. In the past few years, manufacturers have also been looking at bamboo and wood, given their green background (recycling).
Compared to steel, titanium delivers reduced stiffness (half percentage). On the other hand, it is far more difficult to weld or machine, compared to either steel or aluminum. It is also more expensive to extract and process. Titanium delivers an enhanced capacity to absorb shocks than aluminum; however, it is not as light as it.
Titanium tube bikes are made by specialized companies and they are not commonly found in the general production. The typical price for a titanium bike varies according to the features offered; the price range starts somewhere from $1500 and can go easily over $5000. It is rumored that Litespeed is planning on releasing new bike frames made from aluminum at more attractive price