Bicycle Mechanics - How difficult is it to bend an axle?

Here's my situation. I bought some wheels from a friend a year ago. I took the old rear and hung it up in the garage. The frame is now becoming my trainer frame and the new wheels went on a new frame. I stuck the old rear on the trainer frame and discovered that the axle is bent. I don't remember this happening while I was riding the wheel, so it must have occurred while it was hanging in the garage. Granted, I've moved since then, so maybe it got banged around, but is this likely or did I just miss it being bent when I originally took the wheel off?

axles can bent easy if you use to much torque on them or if the bike has fall over or you tighten the trainer to much to hold it in.just to name a few.

..I stuck the old rear on the trainer frame and discovered that the axle is bent. I don't remember this happening while I was riding the wheel, so it must have occurred while it was hanging in the garage.
That is just plain impossible. The loads on a stored bike are so much smaller (for any reasonable method of storage) as compared to the riding loads. It must have happened at another occasion.

That is just plain impossible. The loads on a stored bike are so much smaller (for any reasonable method of storage) as compared to the riding loads. It must have happened at another occasion.

Would it be possible to damage it in the move? It's just weird that I didn't notice anything askew when I took the wheel off initially.

Not possible. You bent it while riding.

Would it be possible to damage it in the move?
Possible - yes. Probable - no. Easiest (read: least hard) way to bend an axle is by exposing it to a load similar to that it'd see while riding. Pretty much the only other option is by exposing it to an axial load, basically pinching it hard between something. And there are few structures around that'd be able to accidentally squeeze a wheel axle hard enough to bend it w/o getting visibly damaged.

Well, it sounds like I need to pay more attention. :o

My dad snapped a rear axle a while back starting to move from a stop because the QR skewer was loosened/stressed.

It took forever to convince the LBS manager that it happened that way, and that the entire wheel didn't need rebuilt.

I had always read that when an axle breaks inside the hub it is usually not obviously apparent, even with the wheel off and the QR skewer removed. Sure enough, I discovered the first broken axle of my life just this weekend when I went to remove spacers from the drive side to install a narrower six-speed freewheel. Even with the non-drive end of the axle clamped in the axle vise, turning the locknut on the drive end caused the visible end of the axle to turn with it. Oops, somethings wrong... There was initially not much play on wiggling the axle but a bit of extra wiggling coaxed it out much like a child's baby tooth.

We have more hills here in Southern Ontario than a lot of people think...

So the OP's axle could have broken a long time ago, from riding absolutely.

I see bent and broken axles on Freewheel hubs but rarely see a cassette hub have a broken/bent axle.

Considering the sort of steel used in these things, I can see that axles may break on occasion due to fatigue. This can happen to highly tempered steel along faults created in the crystal structure. IMHO, this situation could be aggravated by misaligned dropouts, and constant torque could fatigue the axle. The violence needed to bend an axle? Well, I'm not going to try it, but I'd predict that if you were to take an old axle, lay it on an anvil and strike blows on it with a hammer, you be really whaling away before measuring a bend. My guess — and none of my business really — is that your fiend had an accident ... a real prang ... repaired the damage and yet missed the damage to the axle.

Another explanation may be that the axle was locally case-hardened in the area where the bearing race was machined and polished. The outer extremities might then be softer and more vulnerabe to distortions caused by sudden, extreme loads.

In either case, I agree with the some others above that it most likely happened on the machine. The chances of it happening due to transport, and yet without damage to the spokes or the wheel itself are really remote. My two-cents ... interesting case!

The violence needed to bend an axle?
...interesting case!
http://i126.photobucket.com/albums/p92/rswolgast/sherlock.jpg
Indeed.
But have you noticed, Watson, the marks in the concrete floor, here, here, and here? And the damage to the underside of the SUV here, and here? We cannot stay here a moment longer. Miss Whittington is in mortal danger!

Possible - yes. Probable - no. Easiest (read: least hard) way to bend an axle is by exposing it to a load similar to that it'd see while riding. Pretty much the only other option is by exposing it to an axial load, basically pinching it hard between something. And there are few structures around that'd be able to accidentally squeeze a wheel axle hard enough to bend it w/o getting visibly damaged.

I've seen a neighbors bent axle from something striking the axle while the wheel was off a bike. But the greater probability is it was bent from riding and not noticed. I've been riding for several months on one that is bent (5 speed freewheel quick release)-it makes aligning the wheel more dificult and it will eventially bend to the point that it will create some extra friction and eventually snap. This is my last quick release freewheel rear. As they go, I replace my destroyed quick release rear freewheels with bolt on axles for extra strength. I've never had a freehub axle fail nor a freewheel bolt on axle fail.

Indeed. But have you noticed, Watson, the marks in the concrete floor, here, here, and here? And the damage to the underside of the SUV here, and here? We cannot stay here a moment longer. Miss Whittington is in mortal danger!:love::roflmao2::lol::D