Shallower is faster?
04-17-23, 02:07 PM
#26
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Are there any good examples where shallower rim depths (30mm or less) tested faster than deeper sections (30-55mm)? With all of the current wind tunnel data floating about, and the evolution of aero rims from deep V to semi-toroidal to wide, I’m guessing there must be some modern shallow rims that produce less drag than older deep sections, OR, at a certain point does a sufficiently deep rim outperform its shallow counterpart simply due to the increase in depth?
04-19-23, 07:20 AM
#27
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Data no, but anecdotally crosswinds and climbing on a shallower wheel makes more sense. I am a smaller lighter righter and I 100% can spin up a shallow rim faster then a pair of deep carbon wheels. Yes deeper wheels are faster and do have that free weight feel but also require you constantly be putting down watts.
04-19-23, 07:48 AM
#28
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The difference in power required to accelerate deeper wheels is objectively far less than you think. Pros that have measured it found it to be completely insignificant, even on crit courses where there are lots of repetitive accelerations. Only real downsides are crosswinds and very steep/slow climbs where the extra static weight has a marginal effect.
04-19-23, 09:58 AM
#29
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I am not denying the data but as someone who rides deep 65mm carbon rims and also 45mm and 50mm sets but also have ridden 33mm/35mm, the shallower sets for me are simply easier to spin up and more lively to climb. Overall yeah the 65mm deep wheels for me are faster especially with little to no elevation, but we are talking marginally. IMO it all comes down to feel regardless of data
Here is the comparison Swiss-side made with aero and lightweight wheelsets with around 450g weight difference. There was a marginal advantage in lightweight wheels for climbing, due to hauling the extra mass up the mountain. But there was virtually no advantage from the inertial effect of accelerating the wheels (0.7 sec over a 64 min crit race. To put that in perspective, 1W extra power output was worth 5 sec)
https://www.swissside.com/blogs/news...ight?locale=en
04-19-23, 10:33 AM
#30
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04-19-23, 11:51 AM
#31
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I'm mostly interested in what is relatively light, stable and feels good vs ultimate speed in favorable wind / tunnel conditions. Lotta hills around here.
So far, have enjoyed clx 40 clinchers for pretty much everything (especially climbing) on my 15.4-lb rim brake bike and staggered 40/44 or 40/50 ish setups on my disc aero bike (full DA groupset and still a hair over 17.5-lbs with cages and Garmin mount
).
So far, have enjoyed clx 40 clinchers for pretty much everything (especially climbing) on my 15.4-lb rim brake bike and staggered 40/44 or 40/50 ish setups on my disc aero bike (full DA groupset and still a hair over 17.5-lbs with cages and Garmin mount
).
