The use of disc brakes on bicycles is becoming more and more frequent, which has led to the appearance of different axle standards. In this regard thru axles are becoming more and more popular, and are available for both mountain bikes, road bikes and even touring bikes. In this article we help you to clear all your doubts about this bicycle part, we talk about what is a bicycle thru axle, the different types and other questions of interest. Read on!
What is a thru axle?
A Thru Axle (TA) is an elongated, rod-shaped piece that creates a rigid connection between the wheel and the bicycle frame or fork. Unlike the older models (quick releases), thru axles have a larger diameter and a closed dropout, which creates a firmer and more stable connection. The bicycle thru axle has the main advantage of helping to improve riding precision, especially when it comes to mountain disciplines -that’s why they are often referred to as MTB thru axle types- and they are very useful in uneven terrain where a constant geometry of the wheel with respect to the frame is required. In addition, these parts facilitate the correct alignment of the disc brake and minimize friction problems, which increases braking efficiency.
What is a bicycle thru axle and what is its function?
The bicycle thru axle is usually intended for the world of competitive and high-performance cycling because of its ability to better withstand lateral forces without flexing. This facilitates safer and more reliable handling at high speeds and in situations where there is a rapid change of direction, such as technical descents and sharp turns.
What about a thru axle for a roller?
Actually, it is the same type of axle, with the difference of being used to improve the compatibility of the bicycle with a smart roller. This is the case of the Thru Axle 12 mm thru axle, which runs through the entire hub of the bike and the roller, threading in on the opposite side for maximum stability.
What types of thru axles are there?
Thru axles can be of many different types, such as the 12×100 thru axle, the 12×142 thru axle (road) or the 12×148 thru axle. The truth is that we can find them available in different lengths, however, the diameter is the one that is standardized depending on whether the axle goes on the front or rear wheel. Also note that when choosing a thru axle you should pay attention to the thread pitch (generally ranging from 1.0 to 1.75 mm).
Rear wheel thru axle
The standard rear wheel thru axle usually has a diameter of 12 mm, the ideal thickness for improved lock-up, disc brake alignment and other advantages mentioned above. Lengths can vary – generally from 165 mm to 180 mm, depending on the bike and manufacturer.
Front thru axle
The front thru axle has a standard diameter of 15 mm, the most common. This measurement is independent of whether it is a thru axle for road or mountain bike, in the end -as we indicated above-, you have to look at the dimensions of the axle and the thread pitch.
What is a quick release?
The quick-release is another type of axle before the thru axle. It is also known as a quick-release shaft. This part, like the thru axle, is inserted inside the hub, but has the difference that at one end it includes a lever that opens and closes in different positions and a nut at the other end -which is the one that generates tension to immobilize the wheel-. In addition, in between, we can find two springs that keep it separated, so that it fits correctly into the fork. Unlike the precision and rigidity offered by thru axles, these are more complicated to install because if you apply too much force you can over tighten it and then you will have problems to remove it, while if you fall short, the wheel can come off.
Roller thru axle: main advantages
Having clarified what a thru axle is and what types there are, it is important to talk about the main advantages of these parts in summary, and in comparison with quick-release axles. These are the reasons why they have become so popular in recent years:
- They are safer.
- Reduce brake rotor friction.
- Improve braking force.
- They prevent disc brakes from ejecting the wheels.
- They do not bend or break under heavy stress.
- They improve the handling of the vehicle, as well as cornering and stability in general, since they stiffen the front of the bicycle.
- They are more modern.
- They reduce injuries due to user error.
- Prevent bicycle fork fatigue and failure.
- They provide consistent wheel alignment of the bike wheels when removed.
What is the axle size for my bike?
To know what type of axle you need, it is essential to know the specific measurements your vehicle uses. Of course, these are standardized measurements, but there are several types and you must choose the same as your bike. You can choose to look at the technical specifications of the specific model or, on the other hand, measure the axle with a tape measure or a through axle adjustment guide (spanish). Note that the indications usually appear as follows: through axle 12×100 – 1.0. This refers to the diameter, length and thread size, respectively.