Wheel Failure due to missing Cone Spring?



urge2kill

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Aug 13, 2013
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http://www.bike-manual.com/brands/fisher/om/mountain/wheel_qr.html
The article says that the cone-shaped spring keeps the skewer centered in the hub.

I recently had to replace the rear wheel axle, and I lost one of the cone-shaped springs. I started riding without it. A few weeks later, upon starting another ride, it was unusually difficult to pedal. It felt like friction inside one of the wheels, but everything looked fine. "Maybe it's just the wind or the slope..." I got back on, and the friction seemed to have ceased. Suddenly, the friction came back with a vengence, and my skewer snapped. Recovering the lever end of the skewer, I realized that the break was very close to the nut. As I started walking my bike, I noticed that the axle was unscrewing (out the end with derailleur, where the skewer-nut was) as the wheel turned, so I carried it instead.

I am replacing the springs and the exposed-cam QR skewer. While on that subject:
- Can I replace it with any cone-shaped spring meant for bicycle skewers?
- If my rear dropout is 135mm, what length skewer do I need? I already measured the skewer (the metal rod) as 5mm diameter.
- I can go with exposed-cam or enclosed-cam, right? http://sheldonbrown.com/skewers.html
 
The skewer draws the dropouts tight to the lock nuts and 'self-centers', if you will as it does. A tiny little flatwire or roundwire spring isn't going to do anything to resist the clamping force one way or another. All the springs do is keep the QR semi-centered for easier wheel insertion into the dropouts.

- Can I replace it with any cone-shaped spring meant for bicycle skewers? Yes. http://www.bikeparts.com/search_results.asp?id=BPC306184&gclid=COL23sjt2LoCFVEOOgodNHQA_Q

- If my rear dropout is 135mm, what length skewer do I need? I already measured the skewer (the metal rod) as 5mm diameter. One for a 135 OLN axle. Rears are made for 130 and 135 MM. There are 125 MM versions for track bikes that are used on the road and some 140 MM versions, too.

- I can go with exposed-cam or enclosed-cam, right? http://sheldonbrown.com/skewers.html Yes. Just two versions of the same over-center drawbolt clamp.

FTA: There's no way the missing spring caused the failure. More than likely, that was due to over-tightening the skewer repeatedly or a broken axle.
 
I'm sorry, but that edit footnote is really suspicious...
It was ~1 minute after my post in the R,CT,&L thread (which you responded to promptly), and the edit came nearly an hour after the original post was made.

Hypothesis:
But I think you are right that it wasn't the spring. Obviously, the axle has become lodged in the hub, forcing it to turn with the hub, thus its screwing out from the hub when I rotate the wheel. This could be the cause rather than a symptom. As I was riding, the axle would have kept unscrewing, turning the skewer with it. As the skewer lever tightened against the dropout, the friction increased, making it ever more difficult to ride. When the skewer couldn't unscrew any further, it snapped.
 
Error: Indeed, the skewer lever couldn't move any further to the right because it was up against the hanger, but this is when the skewer began to resist from turning with the axle, causing it to screw into the axle ever more tightly. When it couldn't screw into the axle anymore, it snapped.

So yes, it was a case of the skewer being over tightened.