Lately, thru-axles have been adopted on many bicycles.
Even though quick-release (hereinafter "QR") systems are overwhelmingly more convenient for removal and installation, more and more frames are being released that utilize the thru-axle system.
So, what exactly is the reason for this?
In this post, I would like to explore that very question.
First of all, what exactly is a thru-axle system?
A thru-axle system is one of the methods used to attach wheels to a frame.
The QR system, which is currently the most mainstream method for securing wheels, involves placing the shaft located at the center of the hub into the dropouts of the fork or frame, and then securing the wheel to the frame using pressure from the outside.
In contrast, the thru-axle system involves passing an axle shaft through a hole with the same diameter as the axle on the frame or fork, and then tightening a screw integrated into the frame side to secure it.
It is difficult to explain in words, so let’s look at the photos for an explanation.
This is the QR system.
And this is the thru-axle system.
You can see that they are completely different.
Next, what are the advantages of each?
QR system
・Easy to attach and remove
・Fewer standards, resulting in high compatibility and versatility
Thru-axle system
・Higher rigidity and durability due to the thicker axle compared to QR
Although the major advantage of a thru-axle can be written in just one line, its effectiveness is so significant that it has been adopted on many frames.
Naturally, there are also drawbacks.
・Some require tools for attachment/removal, which takes more time than the QR system.
・The axle standards—such as diameter, length, and thread pitch—are fragmented, so it can be difficult just to understand which one your bicycle uses.
However, the benefits are so great that many overlook these drawbacks.
While that is the thru-axle, it is something originally integrated into the fork and frame, so it is not a part you can simply change later.
Therefore, I hope you keep this in the back of your mind and consider it as one of the selection criteria when looking for your next frame.