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Wiping my bike down after a wet ride, I noticed that the left side spokes on my front wheel are tighter than the right side. I don't have a tensionometer but squeezing pairs on each side and plucking spokes around the wheel yields a feeling of increased tension and a tad higher pitch sound of the left side spokes. This is generally so around the entire wheel.

The wheel is a 26 inch Mavic 119. The 32 spokes are laced 3 cross. The 9mm QR axle is fully engaged in the suspension fork's dropouts, and each side of the rim is equidistant to the inside of the fork leg. With the tire still on, can see it seems to run true and centered. The disc rotor is 160 mm Shimano.

Do disc-brake wheels have greater spoke tension on the left, rotor side?

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The side with the disc is dished in more than the other (that is, the spoke flange is closer to the hub's centerline), so yes, I would expect it to have higher tension.

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    I think "does have" would be more accurate than "I would expect it to have" – ojs Apr 13 at 9:29
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    @ojs "Does have" is not entirely correct. It's well conceivable to construct a bike with a slightly asymmetrical fork that compensates for an asymmetrical hub carrying an undished wheel. While there is no way around dishing a rear wheel to make space for an 11 gear cassette because of the chain-line, there are no such space constraints on the front wheel. You could make the front wheel hub extend twenty centimeters further to the left than to the right and still have a perfectly rideable bike. – cmaster - reinstate monica Apr 13 at 20:32
  • @cmaster-reinstatemonica can you point out an existing wheel that the design you propose? A friend of mine wrote an excellent essay about this: nibblestew.blogspot.com. By the way, did you miss the sentence before "I would expect" that I responded to, or did you ignore it on purpose? – ojs Apr 14 at 6:30
  • @ojs My point is that "does have" is not absolutely correct, but "I would expect it to have" is. Sorry, I'm a bit of a mathematics/science person, I have a deep love for absolutely correct expressions. That's why I didn't care whether I know a concrete example of a bike that's been built that way: It's enough that it's possible to violate the "does have". I know I'm being a bit pedantic here, and I most certainly did not mean to attack you in any way. Just sharpening the saw of reason :-) – cmaster - reinstate monica Apr 14 at 7:07
  • @cmaster-reinstatemonica I am an engineer myself, and I recognize the type. For future, I would advise you to check the context before focusing a single detail. Here agree that the hypothetical symmetric disc wheel would have equal tension on both sides, but in context it should be clear that I was writing about asymmetrical wheels. – ojs Apr 14 at 8:41

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