Cross shafts and wheel axles

Why the thru-axle replaced the quick release

The thru-axle passes through closed dropouts and screws directly into one of them. With a diameter of twelve or fifteen millimeters, compared to five for a quick release skewer, it connects hubs or bases into a much more rigid assembly: the wheel no longer flexes during braking or cornering, and it always repositions itself exactly in the same spot. This precision is crucial with disc brakes, where the caliper leaves only a minimal gap around the disc. Born in downhill, the thru-axle has become standard in mountain biking, and has since appeared on gravel and disc road bikes.

The other wheel components

Wheels are also available in:

• Wheel locks.
• Hubs.
• Bearings.
• End caps.
• Freehub body.
• Rims.

All wheels can be found on the wheels page.

Diameter, spacing, threading: taking the right measurements

An axle is described by several measurements. The diameter: twelve millimeters on most road and gravel frames and forks, fifteen or twenty on mountain bike forks. The spacing of the hub: one hundred or one hundred ten millimeters at the front, the latter forming the Boost standard for mountain bikes, one hundred forty-two or one hundred forty-eight at the rear. Finally, the total length and thread pitch, specific to each frame manufacturer: the same E-Thru axle from Shimano exists in several lengths for a given spacing. This information is often etched on the original axle or in the bike's technical specification.

Lever, hex head or home trainer axle

Lever axles, like the Sram Maxle and the Shimano E-Thru, are screwed in and locked by hand, without tools, making it easy to remove the wheel by the roadside. Hex head versions, which are lighter and more discreet, require a tool but do not snag on anything. The Black Bearing axles are replacement parts compatible with RockShox forks, useful after losing or breaking the original axle, and the complete Suntour axle replaces that of the Boost brand forks. The P2R axle for home trainers allows you to attach a bike with a rear thru-axle to the device, thanks to ends compatible with its clamping jaws.

Bargain finds

Great deals can also be found in the bargains, promotions, clearance, sales, and Black Friday. The new arrivals showcase the latest collections, and 24-hour delivery items are prepared and shipped within 24 hours. The major events of the year follow a reliable order: the Black Friday in late autumn, the year-end holidays, the winter sales, the French Days in spring, then the summer sales and back to school.

Frequently asked questions

My thru-axle is stuck: how do I remove it?

Fully open the lever or unscrew with a wrench while applying firm pressure, without forcing a stuck thread. A penetrating oil applied to the thread and left to work for a few minutes often helps. When reassembling, a thin layer of grease prevents the issue from returning.

How do I attach a trailer to a bike with a thru-axle?

You need a specific axle, which is longer, that incorporates or accommodates the trailer hitch, with the same diameter and thread pitch as the original axle. Trailer manufacturers offer versions based on frame standards.

Is a titanium or carbon thru-axle worth it?

It saves a few dozen grams, with no effect on rigidity if measurements are respected. Aluminium and steel withstand shocks better and remain the most sensible choice for regular use.

Are there anti-theft thru-axles?

Yes, some axles tighten with a coded key or a tool specific to the manufacturer. They deter the quick theft of a wheel in the city but require you to carry the tool for fixing a flat.

What does an axle of twelve by one hundred mean?

The first number is the diameter of the axle, twelve millimeters, and the second is the spacing between the fork's dropouts, one hundred millimeters. This is the front standard for road and gravel bikes with disc brakes.