Classtime 

I have a carry freedom large y coming and intend to use it for short surf trips mostly. BUT there will be occasional trips with cement, stucco, etc. Should I replace my quick release axle with a solid one? I am familiar with the 45 vs. 90 kilo limits but I imagine there are plenty of trailers being pulled by the skewers. Has any body broken one from pulling a trailer?

Jeff.

Arcanum

My understanding is that the qr skewer limitation is less one of immediate failure, and more a matter of metal fatigue eventually leading to failure.

In that case, you can get by without a solid skewer, but it is liable to fail unexpectedly.

My recommendation would be to bite the bullet and do the solid axel if you're pulling heavy stuff regularly.

Classtime 

I put in a Wheels Manufacturing 187mm solid axle which gives me room for track nuts with the built in washer gripper things. (an Ultegra 6700 hub). Now, I won't be finding out if the skewer will fatigue and break. I'm thinking now that I might as well replace the front axle to match the rear for aesthetic and security reasons.

FBinNY 

stiffness in steel rods, along with resistance to bending comes mainly form the outer layers (for lack of a better word).

The resistance to bending loads is based on the steel x it's distance from the "neutral axis" or center line between the steel that compresses and that which stretches. This is why structural steel beams have two flanges with a central section keeping them apart. So, the center of a solid axle adds, (and conversely the hole costs) little, strength.

Counter intuitively, a QR axle may be better. It isn't much weaker, but since the skewer is independent and can survive a break, it can act as a safety net holding broken axles together so you can limp home. The fact is that many riders of QR wheels have ridden miles and miles with a broken axle, not known it and gone a bit crazy diagnosing some clicking, until they removed the rear skewer and the two sections of axle fell out.

zebede

I have never broken or bent a hollow crmo axle. But I have bent a number of low quality solid replacement axles (fwiw they were on rear wheels converted to single speed)