What?? I had quick release wheels in the early 80's and they do nothing to the bearings. Are you serious or just stirring the pot?

[MENTION=356408]daviddavieboy[/MENTION], meet [MENTION=234196]mtb_addict[/MENTION].

Only if they make a point of buying special, high-quality axles.
And even then with a marginal amount. For bending, the loads are mostly at the outer layers of the axle. The strength lost from using a hollow axle is very small.

If I worried about safety, I'd make a point of using q/r axles. Plenty of people have finished rides on broken axles with the q/r holding parts together.

Since the QR skewer was invented in 1927 an American sold road bikes over a certain quality level have had skewers since the '70s, I fail to see your point.

As for compressing bearings, proper technique and bearing adjustment solves the problem.

I set my QR's light for roadbikes, a bit more clampish on my classic MTB's. And as said, the QR's do cramp the hub bearings so I go easy. I have never had a safety issue with them.

Locknuts go between the dropouts rather than in the dropouts, but I assume I know what you mean.
And that's due to using wheels with different OLD. Easy enough to fix on cup & cone hubs if it bothers you.

Or are you talking about axles being a sloppy fit in vertical dropouts?
In that case, don't expect too much from TAs.
Since people expect tool-less removal and installation, TAs have to be a fairly loose fit.
TA wheels too are held in place by a part of the hub being pressed against the inside face of the DO.
It's quite common for people to tighten front TAs with the wheel off the ground to prevent the wheel from shifting during braking.

Not that I want to agree with mtb_addict but he is right on one thing: The quick release compresses the bearings when you apply pressure to it. Of course the same can be said of nutted axles since it's the cone that is being pushed inward by the pressure of both systems.

He's wrong on everything else of course.

They have worked for decades without issue on millions of bikes. Nearly every issue with a quick release is due to user error. They aren't "prone" to user error just prone to people being ignorant about how to use them.

You might "chew up your dropouts" but that is by design. Whether the axle is a nut or a quick release, they should have knurling on them that bite into the frame and "emboss" it. Every quick release and every axle nut I've ever seen has knurling on them. And you won't chew up a carbon fiber bike any more than a metal bike since the dropouts on carbon bikes are metal...at least all the ones I've seen.

Full carbon dropouts are pretty frequent. I have them on my fork (alloy in the rear).

Thats the problem with the internet, you can't see the evil grin on the other side of the monitor.

If the cone and lock nut are set right the QR cam should not compress the bearings enough to damage them. That being said, my shimano wheels get rebuilt every winter and I usually get 3 years out of bearings (10,000-15,000 KMS). The lifespan may be due to this compression but I am not sure.

I had a safety issue with a front QR "back in the day" We went camping and I had to remove the front wheel to fit the bike in the vehicle. Later that night I popped a wheelie to impress a girl and the front wheel fell out. Feet in toe clips - the aftermath wasn't pretty - she wasn't impressed.
Operator error forgot to tighten the QR when I put the wheel back in. I'll freely admit copious amounts of alcohol were also involved.

Have you ever heard of an accident due to a QR failure?

IMO through axle is a clearly better system, but not for safety reasons.

The original QR was designed by Tullio Campagnolo himself... enough said.

Are quick release hubs safe? Yes if used properly and no if they aren't used properly. The same applies to a kitchen stove or oven, a lawnmower, a blender, a hair dryer, a carving knife, a can of spray paint, a skateboard, a piece of bubblegum, I could go on and on.

There is a risk that you'll fall going down a set of stairs getting to work. Heck there's risk in just about everything we do in our lives. Should we be worried about a quick release hub? No. If we were, all bicycles, regardless of type, would have training wheels so we don't tip over. And even then, the bike can still tip over.

Tighten it up properly, go ride and have fun!

Maybe I'm just a lucky bast&%d but I've been riding with QR's since '72 when I got my first brand new Peugeot U0-8. Sold it in '85 and bought a brand new Peugeot PH10LE. Guess what. It had QR's as well. Guess what else. I'm still riding that same PH10LE all these years later and I have never had problem one with them. I guess I'm just lucky. And no lawyer lips on either of them.
Jon

It's probably just a matter of people wanting the pro's stuff. I have a QR on my hybrid Peugeot, but when I had a flat there was no mechanic running to me holding a spare with inflated tyre. Without that I don't see the disadvantage of using a wrench.

And it got difficult to get the wheel in tight, I didn't really use that bike for going fast, but pulling the wheel against the stay is annoying. A friend had the same problem recently, but with his road bike at speed and he hurt his knee in the crash that caused.

I know that but therein lies the problem. The cone has to be set right and even when set right, there is compression of the bearings. On the other hand, a nutted axle does the same thing.

The cones have to be adjusted just right REGARDLESS of what type of axle you are using. The adjustment is just different between a QR and TA setup.

From the CPSC recall notice: "Shimano has received one report of the quick release breaking. No injuries have been reported."

This might be the most cautious recall I've ever heard of.

I've gone through quite a few bikes and have had zero issues with QR levers. I've even had axles break on mountain bikes and had QR skewers hold long enough for me to get home on several occasions.

Now that most of bikes I ride have disc brakes, I'd rather have through axles just because it's a little easier to align things right, but it's not like I'm worried about safety. TBH if someone really can't pay enough attention to make sure their QR is set up right they probably shouldn't be riding around to begin with.

What are you talking about, the q/skewer itself?

Set up right, the q/r skewer will only see tension - being pulled at.
And disc brake wheels and Ti skewers aside, it's plenty strong for the job.
If you're talking about the axle itself, then you're poorly informed.
Rear q/r axles are 10 mm, just as solid axles.
And for bending, the loads are mostly at the outer layers of the axle. The strength lost from using a hollow axle is very small.
I-beams weren't invented for the fun of it.
For a solid axle to be a little stronger than a q/r axle, it has to be made out of equal quality steel.
And since solid axles are often found on cheaper parts, that's unlikely to be the case.
But if you enjoy fooling yourself into a false sense of security, don't let me keep you.

I think I said that. On all the through axles I've seen, however, they don't use cone and cup type bearing and thus wouldn't have the same issue as cup and cone hubs. The ones I've seen have all used cartridge bearings which don't need adjustment nor do many cartridge bearing hubs have a way to adjust them.

Fixed it.

Bearing type has nothing to do with TA vs QR. For example, all shimano hubs are cup and cone, their TA hubs are no different. In fact, For pretty much any hub model offered in TA and QR, the bearing type is going to be the same between them.

What you have seen (TA being all sealed cartridge bearing) is probably due to the fact that higher end and/or newer hubs are more likely to be sealed cartridge bearings (Shimano being one exception), and the same is true of TA frames and bikes (higher end and/or newer). It's a correlation thing. Higher end/newer frames and forks tend to have higher end/newer hubs on them.

Cartridge bearings are much more common with through axles because through axles tend to be higher end items.

Looking at Shimano's bearings, I can also see that engineering a cup and cone through axle is far more difficult than engineering one for cartridge bearings. Frankly, it looks like Shimano should have followed others lead as the cost of replacing a through axle cup and cone system when it inevitably wears out is going to be prohibitively expensive.