Everything about Inline Skating Axles

Everything about Inline Skating Axles

Inline skating axles come in two main types: single frame axles and double frame axles.

Single axles
Single frame axles are made of a single piece of metal and are used in most modern freestyle inline skates. They come in an 8mm diameter and are only used for frames that are made out of metal (usually aluminium).

The length of a single frame axle is determined by the outside width of the skate frame, and the entire length of the axle is used.

Double axles
Double frame axles are made of two pieces, one to screw in to the other. They are mostly used for plastic frames like for aggressive skating, or for kids skates. They come in three diameters: 8mm, 6.3mm, and 6mm. 8mm is the most commonly used one, 6.3 mm is only for very oldschool skates and kids skates, and 6mm is exclusively for some Roces brand skate.

The length of a double frame axle is determined by the width of the skate frame, but only the length of the axle minus the head is used. 

8mm, 6.3mm or 6mm?
All modern adult inline skates that are worth buying have 8mm axles. These axles are stronger and last longer.

Back in the 80s and 90s this was different though. Back then most skates had 6.3mm and 6mm axles. 6.3mm was the standard for most brands and only Roces used the 6mm axles. Both these slimmer axles are still used on cheap skates, and children skates.

Allen vs Hex/Torx
Almost all skate axles use the Allen 4mm tool. Allen keys are a skaters best friend. They come with almost all pairs of skates and their abundance is a part of their usage. It is easy to get them when you are in need. The allen keys do strip easily though and if that happens it is a pain to get them loose unless you read more about it in this blog:

Torx are the improved version of the allen key. If there is an axle that uses Torx, then they always use the T25 standard. The only downside to Torx is that they are harder to get by in an emergency "loos axle" situation.

On our website length is indicated by the letter L and an amount of mm behind it. For example "L34mm". This amount of mm indicates the distance between the outside of the frame walls.
Another way to measure this distance, is to measure the axle itself.

Measure single axles: For single axles just take the entire length of the axle. The thread and the little head included

Measure double axles: The length of double axles is more varied because it exists out of two pieces screwing in to each other. That means the length can vary for about 5-10mm. The length of the axle is measured from the inside of the bolt head, to the inside of the axle head. In other words, it is the distance between the points of the axle that actually touch the outside of the frame.

How tight?
Inline skate axles should be tightened pretty tight so that they do not unscrew themselfes. One should also check their axles from time to time again. If you tighten your axle and the wheel then does not spin anymore, then there most likely is an issue with the bearing spacer. Learn more about bearing spacers here:

To remove or replace inline skating axles, you will need tools such as a 4mm allen wrench or a T25 Torq tool. Want to learn more about skate tools? read this blog post: 

Special Editions
There are also special editions of inline skating axles available, such as those that only require one tool to loosen, and rockerable axles (such as FRX and IQon) that allow the wheels to chance position slightly in the frame. Check out all available inline skate axles in our webshop:

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