Over the past three rides three of the 14g spokes on my (single speed) KH36 have snapped in the middle–not at the nipple and not at the elbow. Two of them broke in succession during a group ride yesterday.
The first spoke snapped when I was riding casually on a flat section of sidewalk, and the two snapped yesterday while I was climbing up a rather steep asphalt covered hill.
I’ve never had a spoke break in the middle until now. Has anyone else seen this or have any idea what might cause it?
I’ve lost track of which spoke I broke first, but the two that broke yesterday were adjacent on the right side. I generally mount my 36 by vaulting myself up off the left pedal, so I suspect that such repeated mounting has put more strain on the two that broke yesterday.
Bummer.
Was the tension relatively even all the way around the wheel before this happened?
Were these the black stainless KH spokes or the UDC stainless ones??
I’m not sure about the tension–I tensioned the wheel by ear and by feel. Still, everything felt good before the ride yesterday. I checked the tension for all the spokes when I replaced the first spoke that broke. And, I’ve never heard of spokes snapping in the middle because of bad tensioning–I thought the elbow and nipple are supposed to be the weak spots.
The ones that broke are silver UDC stainless spokes. My KH36 originally came with black 13g spokes. I’m not sure the difference other than the gauge.
I’ve seen spokes break in the middle, but it’s not very common. If all of the spokes are from the same part of the wheel it could indicate a place where something hit the spokes and created a weakness.
I have also seen wheels that just break spokes regularly, and with no apparent cause. At the shop I worked at the only solution was to replace all of the spokes. Some spokes are bad from the factory, and fatigue quickly, leading to random spokes breaking along the length, and not at the bend.
In the first case I would just replace the broken spokes. In the second case you might want to call UDC and see if anyone else has had similar problems with spokes from that batch.
If all three broke in the middle, and you’re not aware of any “mid-spoke trauma” (like something banging into your wheel from the side, in a drop, in the car, etc.), it does sound like bad spokes. I’d replace the broken ones with new ones (from a different production run or product order), then see what happens next…