Do quick release skewers tighten in use?

[Pale Rider]

I had quite a job releasing the skewer on the back wheel of my bike when I put the studded tyres on recently.

It wouldn't come undone with finger pressure, but did when I hooked a small ring spanner over the lever for extra leverage

At least the lever didn't snap, which wouldn't have surprised me.

What I can't work out is how it became so tight.

There's no way it was installed that tight, not least because it would have been impossible to do so with palm pressure.

The skewer is lightly lubed and in good order.

The lever sits in the rear triangle, so cannot have moved.

All I can think is the nut end has somehow tightened itself over time.

I can't remember if I fitted the studded tyres last winter, and I've not had a puncture on the bike for ages, so the lever won't have been released for a year, possibly closer to two years.

Any thoughts?

 

[lpretro1]

No they don't tighten themselves up - you must be stronger than u thought!

 

[raleighnut]

I had quite a job releasing the skewer on the back wheel of my bike when I put the studded tyres on recently.

It wouldn't come undone with finger pressure, but did when I hooked a small ring spanner over the lever for extra leverage

At least the lever didn't snap, which wouldn't have surprised me.

What I can't work out is how it became so tight.

There's no way it was installed that tight, not least because it would have been impossible to do so with palm pressure.

The skewer is lightly lubed and in good order.

The lever sits in the rear triangle, so cannot have moved.

All I can think is the nut end has somehow tightened itself over time.

I can't remember if I fitted the studded tyres last winter, and I've not had a puncture on the bike for ages, so the lever won't have been released for a year, possibly closer to two years.

Any thoughts?

If you closed it in warm weather then it may have contracted slightly in the cold making it just a fraction tighter.

 

[Pale Rider]

[QUOTE 4660200, member: 45"]I think it only takes a little conflict between two surfaces/materials in a skewer for them to start to stick.[/QUOTE]

Mmm, that sounds possible.

So rather than the skewer being too tight, the lever was sticking against the skewer.

We all know seatposts can stick if left for a long time, which the skewer was.

I've just smeared a tiny bit of grease on the lever pivot/bearing surface.

Can't do any harm - it still operates as it should.

 

[S-Express]

If you closed it in warm weather then it may have contracted slightly in the cold making it just a fraction tighter.

Is it not the other way round? If it had contracted, the fitting would be looser, no?

 

[Pale Rider]

Is it not the other way round? If it had contracted, the fitting would be looser, no?

I doubt minor temperature change is a factor here, but the general point is contraction in the cold will make the skewer shorter and, given both ends are fixed, tighter.

Edit: Cross post with User.

 

[S-Express]

[QUOTE 4660280, member: 45"]If the axle itself contracts it will pull the lever in tighter.[/QUOTE]

True, but assuming the other parts of the QR also contract by a similar amount, then it would cancel out?

 

[Ajax Bay]

[QUOTE 4660280, member: 45"]If the axle itself contracts it will pull the lever in tighter.[/QUOTE]

True, but assuming the other parts of the QR also contract by a similar amount, then it would cancel out?

I'm going to assume what @User actually meant to say was that 'if the skewer itself (not the axle) contracts, it will pull the lever in tighter.' If the axle alone contracted (but see below) this would have the effect of loosening the QR.

Though I, too, doubt that this is a 'tighten it warm, try to loosen it cold' cause, what @S-Express is suggesting, I think, is that the steel axle (not the 'other parts of the QR') will contract the same amount as the QR skewer so "it would cancel out". Coefficient of steel is ~12 x 10^-6 so the axle of OLN 130mm would contract 1.56 microns per degree. The QR skewer would contract fractionally more (as the relevant measurement is to the outside of both dropouts (rather than inside - ~143mm)) ~1.72 microns per degree.
0.16 microns is a 'cancel out' in my book, too.

 

[Levo-Lon]

I'm going to assume what @User actually meant to say was that 'if the skewer itself (not the axle) contracts, it will pull the lever in tighter.' If the axle alone contracted (but see below) this would have the effect of loosening the QR.

Though I, too, doubt that this is a 'tighten it warm, try to loosen it cold' cause, what @S-Express is suggesting, I think, is that the steel axle (not the 'other parts of the QR') will contract the same amount as the QR skewer so "it would cancel out". Coefficient of steel is ~12 x 10^-6 so the axle of OLN 130mm would contract 1.56 microns per degree. The QR skewer would contract fractionally more (as the relevant measurement is to the outside of both dropouts (rather than inside - ~143mm)) ~1.72 microns per degree.
0.16 microns is a 'cancel out' in my book, too.

don't forget road salt in the equation. ..I think the heal of the skewer may just be dry when first undone.
and it's a lot easier to shove one home with a palm than pulling it with a finger tip...

as @User says we are a sad lot ...very

 

[User16625]

I'm going to assume what @User actually meant to say was that 'if the skewer itself (not the axle) contracts, it will pull the lever in tighter.' If the axle alone contracted (but see below) this would have the effect of loosening the QR.

Though I, too, doubt that this is a 'tighten it warm, try to loosen it cold' cause, what @S-Express is suggesting, I think, is that the steel axle (not the 'other parts of the QR') will contract the same amount as the QR skewer so "it would cancel out". Coefficient of steel is ~12 x 10^-6 so the axle of OLN 130mm would contract 1.56 microns per degree. The QR skewer would contract fractionally more (as the relevant measurement is to the outside of both dropouts (rather than inside - ~143mm)) ~1.72 microns per degree.
0.16 microns is a 'cancel out' in my book, too.

Jesus Christ!! Are you an engineer? Assuming that is true then that is really brainy type stuff.

 

[User6179]

I think it is just easier to push than pull , if you push the lever shut with a decent amount of force then it will feel you need to use a lot more force to open it but in reality it is because it is easier to apply more force pushing than pulling .

 

[Ajax Bay]

Assuming that is true

This is 'CycleChat' you know. Each to their own.

 

[midlife]

Coefficient of static versus sliding friction once it stops it's harder to get it going again ?

Shaun

 

[Flying Dodo]

Last year, on a local ride I was leading, someone found their rear wheel locked up, just as they were slowing down. The skewer was very tight and after loosening it, I found the cone nuts on one side were rather tight. After loosening things a bit, and doing the skewer back up again, he set off again, but found the wheel locked up again very quickly. This time the skewer was on so tight, the lever snapped when trying to open it, so he had to bail. So something was screwing the axle the other way, to make the skewer tighter.