Thanks for your input, Sander. I appreciate it, especially given your experience with different wheel builds.
Out of curiosity: what’s your take on the stiffness of a 20/20 setup with 3.1mm spokes for a rider in my range?
I agree tire rub isn’t just a wheel issue. For context, this is on a Lightcarbon LCR018D. I’ve also used the wheels on another frame with more clearance. No rubbing there, but the rear still felt relatively flexible under load (subjective, but noticeable).
On the Lightcarbon, I can deflect the rear wheel into the chainstay by hand without excessive force. Combined with the audible “working” under sprint load, that suggests to me the rear wheel isn’t meeting my requirements.
I understand the ways to increase stiffness (thicker spokes, more spokes, different hub), but I’m trying to determine something more fundamental:
is this behavior expected for this configuration, or is my rear wheel an outlier?
I specifically chose this rim (135kg system limit) to have a reasonable margin for strength and stiffness at my weight/power. If this setup is inherently at its limit for riders like me, that’s useful to know, but then it’s more about application clarity than a one-off issue.
So my main goal here is to understand: is this a design limitation, or a product-specific problem?
Perfect — your hub actually explains why your wheels feel solid even on 3.1 mm spokes. You’ve got a much stiffer system, not just a different spoke count.
Here’s your final reply with your hub comparison added properly and factually:
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Yeah, I think there are a couple of things getting mixed together here: what you can do to a wheel by hand, and how it behaves under real riding load.
You can deflect pretty much any wheel far enough by hand to touch a chainstay if you try. I can do it with my own wheels too, and those ride completely fine under power. That kind of static test just isn’t a reliable indicator of real-world stiffness.
When you’re riding, the wheel is rotating and loads are distributed dynamically through the spokes. That’s very different from applying a static sideways force with your hands. All wheels flex — that’s normal. What matters is how they behave under load.
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Where things become clearer is the actual build and hub configuration.
Your setup:
* 20 front / 20 rear
* 1:1 lacing (10 per side)
* 3.1 mm spokes
* fairly standard flange geometry (around 53 mm / 42 mm rear)
For example my setup on a set of wheels with R2 hub (also 3.1 mm spokes):
* 21 front / 24 rear
* 2:1 lacing
* rear: 16 spokes drive side / 8 disc side (3-cross on drive side)
And importantly, my hub geometry is very different:
* Rear drive-side flange: 74 mm (very large)
* Rear disc-side flange: 45 mm
* Asymmetric flange design
* 56 mm flange spacing
That makes a big difference.
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Why this matters
1. Spoke count (rear)
Going from 20 → 24 spokes = +20% spokes
That alone improves how load is shared and increases lateral support. It’s not a perfect 20% stiffness gain, but it’s significant
2. Flange diameter (huge factor)
Your hub: ~53 mm drive side
My hub: 74 mm drive side
That’s not a small change — that’s a massive increase in bracing leverage.
A larger flange increases the bracing angle, which directly improves lateral stiffness. This is one of the biggest contributors to how “stiff” a wheel feels under load.
3. Lacing pattern
* Your wheel: 1:1, evenly split
* Mine: 2:1 with more spokes on the drive side + 3-cross
That puts more structural support where the torque actually is (cassette side), which improves resistance to flex under sprinting.
Spoke thickness trade-off
* 3.1 mm spokes ≈ 2.1 g
* 3.95 / 5.1 mm ≈ 3.5 g
Total saving: ~50–60 g
But:
* 3.1 mm ≈ 80 kgf lateral rigidity
* 3.95 / 5.1 mm ≈ 115 kgf
→ ~40% increase in stiffness capacity for basically a gel’s worth of weight
Putting it all together
Your setup:
* low spoke count (20/20)
* thinner spokes (3.1 mm)
* standard flange geometry
* even spoke distribution
My setup:
* higher spoke count (24 rear)
* much larger drive-side flange (74 mm)
* asymmetric 2:1 lacing
* better bracing angles
Even though we’re both using 3.1 mm spokes, the overall system stiffness is not comparable.
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Bottom line
I don’t think your wheel is defective.
I think you’re hitting the limits of a very lightweight configuration (3.1 mm + 20/20 + standard hub geometry) at your power level (85 kg /1300 W).
- Hand-flex test not meaningful on its
Real load behaviour that’s what matters
Your symptoms (flex, noise, rub) consistent with a stiffness limit
If you want to fix it, the biggest gains will come from:
* more spokes (24h rear or more)
* or thicker spokes
* or both
