Tullio Campagnolo: Inventor of the modern quick release.

Step 1
Insert the wheel in the fork or rear stays' drop-outs. Ensure that the wheel is centred in the dropouts. There should be even spacing between the two brake shoes and the rim. If your brakes are properly adjusted so that they are exactly even-spaced when the wheel is in place, you may use the brake to hold the wheel in place for subsequent wheel fitment. However this step only works if you don't have retention tabs on your fork.

Open the QR lever so that it is inline with the wheel's axle as in the photo below.

The first step is to hold the QR lever in line with the axle.

Step 2
Hold the open lever of the QR with your one hand and with the other hand screw the QR's nut until there are no more gaps between the various components of the QR and the wheel's jamb nuts. At this stage the lever is still held in the in-line position. You can turn either the lever or the nut, but holding the lever stationary will ensure that you can control its final position, which will be, in the case of the fork, in the upright position in line with the fork leg and in the case of the rear wheel, pointing backwards or upwards in line with the seat stay. If you turn the lever its final resting place is random, ending up with it pointing in an undesired direction when closed.

Remove all space between fork, wheel and QR.

Tighten the nut with the lever in the open position.
You may need to hold the lever.

Step 3
Now close the lever. It should be hard to close - hard enough for the lever to leave a white indentation on the palm of your hand when you're finished. As the lever closes, you should feel it move with difficulty and as it moves towards the closed position, it will suddenly move easier and then softly settle into place past the most difficult part of the move, just off the vertical leaning over to the fork. This means the QR lever has gone past the highest point on the cam and settled in a position where it cannot open by itself. In order to open it again you have to move it past the hardest point of the arc again, something that will not happen by itself or accidentally.

This QR is incorrectly closed. The lever still has to move past the highest point on the cam.	This QR is closed correctly. Notice how the lever lies snug with the fork leg.

Do Not:
Never attempt to tighten the QR by winding up the QR lever, essentially using it as a one-eared wing nut. The process should always finish with a very tight closure of the open QR lever.

Do not tighten the QR by winding up
the lever using it as a wing nut.

Quick Release Components.

An aluminium QR nut on the left and steel on the right. Steel is preferable.	Conical QR springs. These help centre the QR on the wheel and help with quicker installation.	The conical spring's correct position on the QR. Note the steel insert in the plastic cup.	Side view of QR nut. Adjustment on the frame happens through this part.

The hub without QR. Note the hollow axle and knurled jamb nut	Note the cam on the QR lever. This is the part that tightens and ensure that it stays that way.	The best QRs are of the enclosed cam type.	Good QR levers are clearly marked Open and Close.

Types of Quick Releases .

Bicycle Quick Release closures are available in two broad types. Enclosed cam and open cam types. Of the two, the enclosed cam type is by far the better QR. Unfortunately the current tendency to cut weight on all components has seen wheel manufacturers favour the open cam type since they can be made a few grams lighter. This is not a component where weight saving is more important that safety or longevity. You sacrifice safety, reliability and operating smoothness with open cam types of QRs.

Two types of QRs. Internal cam on the left
and external cams on the middle and right models.
The one on the far right even features a bottle opener.

Shimano and Campagnolo both only make internal cam QRs. Their QRs may well weigh a few grams more than boutique QRs but are infinitely better. The bite parts are made from steel, not aluminium. This gives a more secure grip on aluminium frame drop-outs. The cams are made from steel for longevity and they are enclosed in a housing, protecting them from the elements.

Open cam QRs on the other hand use aluminium cams which have to move against something softer - plastic. This is often crushed, compromising the QR's safety.

Shimano and Campagnolo has gone to great lengths to keep their QRs to maximum strength, yet keep weight down as much as possible. This is evident from the steel threaded inserts housed in plastic or aluminium nut cups. This keeps the bit part hard and saves weight where hardness is not required.

How Quick Releases Fail.

QRs generally fail by the skewer rod breaking off at the threads. This is because the thread is the weakest point on the rid. Another mode of failure is the threads in the nut stripping. However, this only happens in inferior QRs where the nut is made purely from aluminium. The good news is that a QR will not fail during a ride but fail upon closure, giving the cyclist warning of a failed part. This is thanks to the cam design. The most difficult part of the closure precedes a slightly relaxed swing of the lever and the skewer or nut will fail before the lever is fully closed.

The typical place where a QR tie-rod will break.	The top tie-rod shows evidence of stripped thread in the nut, whilst the bottom one broke off.