presta
Guru
Going uphill, weight saved off the rims won't be any better that the same weight saved anywhere else, you only get additional benefit from the moment of inertia whilst accelerating.go-faster-hoops to get up that hill 1% faster
Going uphill, weight saved off the rims won't be any better that the same weight saved anywhere else, you only get additional benefit from the moment of inertia whilst accelerating.go-faster-hoops to get up that hill 1% faster
Indeed - I'm not questioning that the difference is tangible; more the value of chasing such marginal gains in terms of the associated financial cost and the real-world worth to the average cyclist.I don't know but I can tell the difference between 32h traditional training wheels vs rs10 and vs DA c24 /c35 / c50
You have to be particularly daft to argue no difference between them.
But you wouldn't want to commute or tour on DA c24.
Nor would a century in 6hrs on 32h / marathons on a warm summer's day make for pleasant ride.
Absolutely -manufactured demand springs to mind.Kings new clothes comes to mind. You're right, keeps lots of cycle component companies in business.
I'd love to see that claim assessed with scientific rigour; I suspect the only way that could be true under objective conditions is if the route is festooned with lots of accelerations / decelerations..Not too long ago there was a lad on the Trek sub-reddit who claimed to have changed his standard wheels for some lighter ones (can't remember what) and gained almost 3mph on his average speed. Amazing!
Indeed - I'm not questioning that the difference is tangible; more the value of chasing such marginal gains in terms of the associated financial cost and the real-world worth to the average cyclist.
Unless you're competing against other cyclists the only person to beat is yourself; and in that case where's the legitimacy in buying your way to victory?
Absolutely -manufactured demand springs to mind.
I'd love to see that claim assessed with scientific rigour; I suspect the only way that could be true under objective conditions is if the route is festooned with lots of accelerations / decelerations..
I can believe that to go from stock wheels to lightweight / aero wheels might feel like that 1mph per level of change imho.
Perhaps; but again cost, real world benefit etc..
Can't be arsed to watch the vid but I've done the calcs in the past. From an acceleration perspective rotating mass is disproportionately influential, as you have to accelerate it both linearly and angularly.. so a given mass saved from the rims will have a greater effect on acceleration than the same mass removed from the frame, for example.
As the chap at the beginning of the vid states, input energy isn't lost, it's stored - lighter wheels will accelerate faster for a given energy input, but also decelerate faster. This matters on a course with lots of speed changes (so something tight and twisty) and of course if you're actually concerned with speed. On something like a tourer where you're coasting a lot and anticipating stops in advance it's less of an issue.
Wheel mass also affects gyroscopic stability, with less rotating mass potentially making the bike feel more responsive but also less stable..
From my own personal experience with modern wheel-set's in the last few years:
I have Hunt 32 UD's on my Wilier road bike which are reasonably shallow and that bike does accelerate noticeably quicker than my other two road bikes but maintaining anything above 25 - 30 mph is also noticeably more watt-consuming than with my Zipp 404's. It's my go-to bike for very windy conditions and long climbing days. It's light and agile.
On my Trek road bike I have a pair of Zipp 404's and at 58mm they are lovely for sprinting with and maintaining higher averages. For sprinting you want to be able to maintain the speed you build up to for as long as possible and circa 60mm or thereabouts is the sweet spot depth for acceleration vs holding speed. My Pinarello road bike has a choice of Dura Ace C50's and Zipp 454's.
So...there is a clear and noticeable difference that the average non-pro 55 yr old can appreciate between a 32mm and 58mm deep wheel-set where there is only about 200g weight difference. This isn't marketing, this is User-verified fact.
How much that difference means to the individual though very much depends upon what type of cycling they do. Obviously, Club and racing cyclists will appreciate it whereas a Commuter or Tourer may not given their bikes typically have other design priorities and speed isn't a thing as such.
The difference between the C50's and 454's is more subtle. There we are only talking about 8mm in depth difference so the advantages of the 454 are that their wavy design from shallower to deeper allows them to have a mix of characteristics and behave like a much shallower rim - you effectively get a 40-45mm wheel-set's acceleration, weight and cross-wind handling with a 58mm wheel-set's ability to hold speed and save watts. Again, an average cyclist can notice the difference but it is only at speed and whether that difference is worth it depends upon needs and goals.
Many for whom these differences won't matter much, if at all, and who have never actually ridden 1000's of miles in trying them, like to think that it is all marketing nonsense and only relevant to Pro's where marginal gains can make a more significant difference. They are however, wrong. Average cyclists can feel the difference and it can have a noticeable effect upon how a bike handles and how much they enjoy riding it for a given course.
I can believe that to go from stock wheels to lightweight / aero wheels might feel like that 1mph per level of change imho.