Ready to take your bicycle maintenance skills to the next level? Then you’ve come to the right place. This simple guide will explain all you need to know about bike quick-release skewers and show you how to choose the right ones. Let’s get rolling and level-up your cycling knowledge!

What is a quick-release skewer? (and why are they so good?)

The job of a quick-release skewer (AKA a QR skewer) is to secure the wheels onto the bike.

A quick-release skewer works by sliding the steel rod through the wheel hub with the skewer ends slotting into the fork-ends (for the front wheel) and the dropouts (for the rear wheel). The lever-and-cam assembly on one end then tightens the skewer pinning the wheel into place.

Legend has it that QR skewers were invented by a pro rider in the 1920s who was frustrated by the wingnut wheel fixings in use at the time. This was a particularly vexing issue because race bikes in those days had two gears. Selecting a different gear from the one you were currently in meant:

1. Stopping and getting off the bike
2. Unscrewing the wingnuts holding the rear wheel
3. Removing the wheel, flipping it over and slotting it back into the frame
4. Re-tightening the wingnuts
5. Getting back on the bike and attempting to catch up again with the other competitors

Clearly this was a frustrating challenge and it was made even more so when fingers were cold and wingnuts were stuck.

Fast forward to today and, whilst we now have multiple gears and easy derailleur-enabled gear changing (and most of us aren’t typically pro riders), QR skewers are still the norm. Why?

I think there are two main reasons.

Firstly, we’re creatures of habit. We like what’s most familiar to us. We like the restaurants we like, the vacation desinations we know, and we like our bikes to have the QR skewers that we know and love.

Second, QR skewers have a major benefit over other types of wheel securing methods – you don’t need to track down and use a tool in order to take off, and re-fit, a wheel.

This is a huge advantage and means that, apart from some fairly specialist mountain bikes, QR skewers are the standard.

What are the downsides of quick-release skewers

It’s not all upside with QR skewers though and there are a few disadvantages that it’s useful to be aware of so that you can safeguard you and your bike.

Bike wheels can be stolen

Because QR skewers can be opened and closed without the use of tools, it means that they can be a target for opportunistic thieves who might be on the lookout for bikes with expensive wheelsets.

There are two ways to prevent your wheels from being stolen:

If you’re leaving your bike unattended, then make sure you use a bike lock that can be looped through both of the wheels. That way, even if the wheels are taken off the bike they won’t be able to be taken away.

Secondly, you can replace your existing QR skewers with a lockable set. These prevent wheel removal by thieves but do mean that you will need a ‘key’ to remove the wheel yourself.

QR skewers can come loose

If QR skewers aren’t securely tightened when fitted they can loosen through normal cycling – especially if you’re cycling over rougher terrain.

It’s important to make sure that the skewer levers are tightly fitted and that you check they are firm before setting off on a bike ride. This pre-flight check is good practice to do as part of a quick look over your bike to be certain it’s all in good working order prior to every cycle.

QR skewers can be incorrectly fitted

One of the most common mistakes with quick-release skewers is not fitting them correctly into the fork-ends or dropouts.

When you’re re-fitting a wheel back onto your bike with the QR skewer it’s essential to make sure that the skewer rod ends are positioned fully inside the rounded slots on the front wheel fork-ends and/or the rear wheel dropouts.

If one or both ends of the skewer are not fully inside the slots then your wheel will not be held securely and this will likely cause an accident and potentially serious injury.

QR skewers may not be suitable for very aggressive riding

QR skewers are very strong and are suitable for most bikes and most bike riding. That said, for very aggressive styles of riding they may not be durable enough (think: fast downhill mountain biking or cycling over big jumps).

For riding like this, a bike that has wheels secured to the bike with thru axles instead may be more appropriate.

If in doubt, check with your local bike shop – show them your bike, tell them what type of riding you do and ask their advice.

Quick-release skewer sizes

Are all quick-release skewers the same size? Sadly not. Life would be too easy if they were, wouldn’t it?!

That said, there are sizes that are much more commonly used than others.

There are two dimensions to be aware of with QR skewers:

• The skewer rod diameter
• The effective length of the skewer

Skewer rod diameter

Most bikes are fitted with skewers that have a rod (the metal pin that goes through the wheel hub) that is 5mm in diameter.

Effective skewer length

The overall length of the skewer is made up of the adjusting nut, through the skewer rod, and the lever-and-cam nut.

The ‘effective’ length of the skewer is more important however.

The effective length is the measurement of the skewer rod where it protrudes from the inside faces of the two end nuts.

It will normally be the case that the front wheel skewer has a shorter length than the rear wheel skewer – to take account of the extra width for the rear cassette (think: the rear gear cogs).

Most bikes will take a front wheel skewer that has an effective length of 100mm and a rear wheel skewer that has an effective length of 130mm (road bikes) or 135mm (MTB).

How to check what size QR skewer you need

The best way to be certain what size skewer you should get for your bike is to measure. Here’s how.

1. Use a pair of digital calipers (ideally, or a ruler and a sharp eye)
2. Undo the QR skewers and take off the front and rear wheels
3. Check the diameter of the skewer rods with the calipers
4. Measure the distance between the outside faces of the fork-ends (where the front wheel goes)
5. Measure the distance between the outside faces of the rear dropouts (where the rear wheel goes)

Make sure you get all these measurements in millimeters.

Compare this information to the following chart and you’ll see which quick-release skewers will fit your bike.