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I've got a gravel bike, and since I sometimes take it on road rides, I am thinking about getting a set of carbon wheels with road tires to swap out with the knobby tires I already have which work great on trails.

From the reading I've done so far, it seems like a 28mm tubeless setup with 40-50mm rim height is a good modern "general use case" setup for a road bike. I know wheels like this may be overkill for a gravel bike, but I am interested in having an upgrade path if I should want to get a road frame later on.

What I am wondering is, what is the difference in performance between say a 1000 EUR wheelset and a 3000 EUR wheelset? Beyond weight, which aspects of a carbon wheel contribute to it's performance, and where is the best price/performance reached?

For instance, I'm looking at the Zip 303S wheels - they seem to tick all the boxes, and the price seems reasonable compared to other comparable wheelsets for a well-known brand, but would there be an advantage of going with a higher end model? Or else could I get the same performance and reliability with no-name Chinese wheels?

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  • Does your bike have disc brakes or rim brakes? If rim brakes, is your existing wheelset carbon as well? otherwise you'd reasonably limit yourself to wheelsets whose recommended brake pads are OK to use with aluminium.
    – chichak
    Jul 9, 2022 at 11:33
  • My bike has disk breaks, and my existing wheelset is aluminum
    – sak
    Jul 9, 2022 at 12:16
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    Swapping between wheelsets can be more difficult than it seems at first. It often requires you to adjust the brakes and rear derailleur.
    – Michael
    Jul 9, 2022 at 12:24
  • Can you specify particular makes and models, please? As in every other industry, it should be the case that more expensive items are better but equally, "should" is the operative word… Jul 9, 2022 at 20:31
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    Proud user of named Chinese wheels that I buy direct from the manufacturer. They're not all no-name 👍 Jul 9, 2022 at 23:19

2 Answers 2

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First, I wouldn't recommend buying from Aliexpress brands that you don't know at all. There are some mainland Chinese brands that sell on Aliexpress or other channels that are likely to be trustworthy. I have a pair of Light Bicycles rims, and that company has some distribution centers in the US and EU. Sensah, Winspace, and BTLOS are some other brands that people I trust think are OK.

In general, if you're comparing name-brand wheels (e.g. Zipp, Enve) to off-brand ones (e.g. BTLOS, Light Bicycles), these are the differences that I'd expect.

  • You're paying some premium for the brand name. If the brand sponsors any athletes, you're paying for that (Zipp and Enve are prominent examples).
  • You're paying for research and development costs. An off-brand wheel company might simply copy or approximate the rim profile of branded wheels.
  • That doesn't mean that the off-brand company would have zero R&D costs. They still need to know how to construct a layup schedule that produces the desired rim shape. Alternatively, an off-brand company might put some work into designing its own profiles, but do fewer steps. For example, they might just do CFD and forego wind tunnel testing. Branded wheel companies almost certainly provide prototypes to sponsored riders to solicit feedback, and off-brand wheels might forego this.
  • Many branded wheels are offering free crash replacements. Think of that as insurance, and part of the price difference is the insurance premium. However, realize that carbon is pretty tough, and off-brand rims are likely to be relatively cheap. For example, on Wheelbuilder.com, ENVE rims retail near US$1,000, whereas most Light Bicycle rims retail under US$300 (plus cost of spokes and labor). The general principle for insurance is that the premium is clearly worth it if you can't afford to replace the insured item out of pocket, e.g. your health. I'd argue that insurance for a discretionary item isn't clearly a must-buy.

As you move up the price spectrum within the same brand, this is what I think you're getting.

  • For rims, you often get lighter weight. A layup schedule means what bits of carbon fiber go where. A more complex layup can save weight by optimizing the shapes, but probably means more pieces and more labor to lay them on the mandrel. Also, the manufacturer might use a greater proportion of lighter (higher modulus) carbon fiber in the premium rims.
  • The manufacturer might put more R&D into the more expensive rims.
  • Similar principles might apply to other wheel parts. For example, maybe the manufacturer uses round spokes for less premium wheels, or uses cheaper and heavier bladed spokes (e.g. Sapim CX Sprint vs CX-ray).

The differences in actual performance as you go up the price ladder could only be measured if you did wind tunnel or field testing. For the most part, these comparative tests aren't public. However, I suspect that many wheels are within single-digit watts of each other.

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    I think the last sentence sums it up superbly - single digit Watts. The question then becomes "does it matter"?
    – mattnz
    Jul 9, 2022 at 22:54
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    Farsports is another brand that I've had lots of success with. (8 wheels) Jul 9, 2022 at 23:20
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    Are you sure off-brand companies even bother with CFD? Getting that right for a rotating wheel is by no means trivial, and without confirming wind tunnel tests it's very easy to get something wrong and not get better results than from just eyeballing it from competitor designs and doing some sanity power-at-speed checks. More important IMO would be FEA, because if they can't afford extensive destructive testing I'd be concerned that there are weird unexpected failure modes. Jul 10, 2022 at 15:45
  • @leftaroundabout no, I am not sure! That is what I was trying to convey with phrases like “I think” and “might do”.
    – Weiwen Ng
    Jul 10, 2022 at 22:52
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  • most important for aerodynamics are the cross section profile of the rim and how well it fits together with the tires, the bike and you. The cross section is much more than the height of the rim.
    Generally rims have gotten wider to match the width of the tires (which themselves have gotten a lot wider) and good rims profile will be more of a U than a V. This avoids turbulences on the trailing rim edge when you have wind that is not exactly from front or back.
    That said, all argumentation about aerodynamics is guesstimating at best, experiments give the only valid answer. Fluid simulations will work to some extent, but they're not really feasible for most people.
  • if you have rim brakes the brake track is vastly different from wheel to wheel. Dry braking performance is usually at least OK, wet breaking performance is all over the place. Look into the specific set.
  • moment of inertia (about the rotation axis): this is how hard it is to accelerate the wheels' rotation, analogue to the mass for linear acceleration. Less inertia means it's easier to accelerate and will reduce steering forces. For the inertia the mass of the rim is most important: inertia is essentially mass times (distance to axis)².
    Tests that address this usually give the energy needed to spin up to some speed. This is equivalent to stating the moment of inertia, as E=J·ω²=J·(v/r)²
  • there's finer and more costly optimisations like ceramic bearings.
  • stiffer wheels handle better and with rim brakes avoid brake rub when sprinting.
  • there are differences that are mostly aesthetic: beside the looks it's mostly the sound, most important: resonance of the rim and the buzzing of the free wheel

I wouldn't buy no-name wheels since wheel failure is pretty catastrophic. I wouldn't make a difference per se between western and chinese brands, however you'll probably find more tests for established western products (which may as well be produced in china...).

By the way, recommendation for specific products are against the rules of the site: don't expect these kind of answers :)

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