You would be hard-pressed to enter a bike shop or Reddit thread and not hear conversations about rotating weight. Rotating weight is the weight of any part of your bike that rotates, such as your wheels, tires, cranks, and cassette. It’s said that reducing rotating weight is equivalent to 2x non-rotating weight, such as your frame and fork. The reason is that rotating weight has to be accelerated and decelerated every time you pedal, which takes more energy than non-rotating weight.
However, there is some debate about whether rotating weight is that important. Some studies have shown that reducing rotating weight can lead to significant performance improvements, while others have shown no difference.
So, what is the truth? Here is a look at the evidence:
The Takeaway
When you look at the physics within the context of cycling, rotating weight makes no measurable difference at all according to Jean Paul Ballard from Swissside. This was based on their testing of two wheelsets that had a difference in weight of 400 grams. Shedding weight does help in terms of efficiency, but rotating weight vs static weight is the same! So yes, putting a premium on rotating weight in cycling is BS!
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