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Does rotating weight really matter?

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Does rotating weight really matter?

Old 05-03-21, 11:06 AM
  #51  
terrymorse 
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From the usenet archives:

Although it may seem daunting, when another rider pulls away on a hill
or in a bike race on the flat, these accelerations, except in standing
starts, are so small as to make the rotating mass story a hoax. Sure,
the mass counts twice as much when accelerating but two times zero is
still zero, and how long does a rider accelerate. Weight of bicycle
components for climbing is the main consideration, not acceleration.
The rotating mass story is a fable that sounds good and has just
enough technical truth to be one that will probably sustain itself
indefinitely
. Making equipment choices by it are a matter of faith,
not fact. ó Jobst Brandt, 26-Mar-2000
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Ride, Rest, Repeat
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Old 05-03-21, 11:09 AM
  #52  
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Originally Posted by sced View Post
Riding a heavier / less efficient bike has merits
Not if you want to enjoy yourself.
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Old 05-03-21, 11:34 AM
  #53  
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Originally Posted by bruce19 View Post
I'm not crazed about average speed. I do, however like it when what is advertised is what is delivered. And, at age 75 I know full well it''s the journey and not the destination.
​​​​​​You're saying these companies are lying about what their wheels weigh? Because this thread started off with you thought the benefits from light weight stuff wasn't enough to justify the price, but now it sounds like fraud (false advertising) is going on??
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Old 05-03-21, 11:44 AM
  #54  
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Originally Posted by Seattle Forrest View Post
​​​​​​ Because this thread started off with you thought the benefits from light weight stuff wasn't enough to justify the price,
That's not accurate. I posted a video. I did not comment.
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Old 05-03-21, 11:50 AM
  #55  
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Originally Posted by hubcyclist View Post
but I think generally folks are looking for a tangible benefit when they decide to shell out cash on wheels and higher priced bikes. So itís fair to temper peopleís expectations. Iíve seen videos where the time savings of nice carbon wheels vs basic aluminum wheels is about 1min per hour, I certainly canít justify spending that much.

I have the most basic of bikes, a base model allez with Claris and axis sport branded wheels and I get lots of enjoyment on the bike, the only limiter is me. And I go way faster than a lot of folks because Iíve put in the work on myself. I think a lot of people buy into hype and then come up with nebulous things to justify spending way too much in absence of any tangible benefits they may have been looking for. Yeah itís all about fun, but I think most folks have priorities outside of cycling and helping people make smart purchases is just as important as getting enjoyment.
​​​​​​Would it be fair to summarize this as "I don't think the value other people will get out of expensive things justifies their price?"

It sounds like you're thinking the only thing any bike equipment can do for anybody is make you faster. But you've seen how disc brakes took over road cycling, the time savings is zero. Negative time savings if the wind is coming from the rotor side. A lot of people will never buy a rim brake road bike again and are happy about it. I've seen a lot of people complain that they can't get high end wheels anymore, I've never seen anybody complain that riders can't spend money on increased safety on the basis of minutes saved per hour.

I have not especially light, but deep, carbon hoops. The main benefit I get out of them is I enjoy riding more when I use them. Did they make me faster? Yes. Do I care? A little. Mainly I like the way the bike feels, looks, and sounds (when I'm going fast). Would I do it again? **** yeah!

Sometimes it's really fun to be fast, but there's so much more to cycling and the difference between 27.3 and 27.4 mph doesn't really affect my smiles per mile.
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Old 05-03-21, 11:51 AM
  #56  
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Originally Posted by bruce19 View Post
That's not accurate. I posted a video. I did not comment.
You just said it's upsetting that people aren't getting what's advertised. Can you elaborate?
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Old 05-03-21, 03:12 PM
  #57  
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Originally Posted by Seattle Forrest View Post
You just said it's upsetting that people aren't getting what's advertised. Can you elaborate?
You said "Because this thread started off with you thought the benefits from light weight stuff wasn't enough to justify the price," That's not what I started off with. I will agree that the "benefit" real or imagined does not justify paying $2,000 or more for a CF wheel set. But, that's just me. If someone else does feel it's justified....go for it. Also, I did not say anything about lightweight "stuff." The video addresses wheels, not stuff. My question is about rotating weight vs weight in general. But, that's just my question. I thought the presenter raised some interesting questions.

Last edited by bruce19; 05-03-21 at 03:32 PM.
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Old 05-03-21, 03:19 PM
  #58  
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Originally Posted by bruce19 View Post
You said "Because this thread started off with you thought the benefits from light weight stuff wasn't enough to justify the price," That's not what I started off with. I will agree that the "benefit" real or imagined does not justify paying $2,000 or more for a CF wheel set. But, that's just me. If someone else does feel it's justified....go for it.
Sooooooo what benefit is being advertised and unmet, with regard to rotating weight? Or is this not really a rotating weight thread and simply another "kvetch about products that cost more than I want to spend" thread?
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Old 05-03-21, 03:40 PM
  #59  
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Originally Posted by WhyFi View Post
Sooooooo what benefit is being advertised and unmet, with regard to rotating weight? Or is this not really a rotating weight thread and simply another "kvetch about products that cost more than I want to spend" thread?
It is a video. Take from it what you will.
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Old 05-03-21, 03:53 PM
  #60  
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Originally Posted by bruce19 View Post
It is a video. Take from it what you will.
I'm talking about *your* statements -

Originally Posted by bruce19 View Post
My take away thus far is that there has been a lot of money spent for not much gain.
Originally Posted by bruce19 View Post
I do, however like it when what is advertised is what is delivered.
So, what's being advertised and unmet w/r/t rotating weight?
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Old 05-03-21, 04:09 PM
  #61  
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Originally Posted by bruce19 View Post
I do, however like it when what is advertised is what is delivered.
What being advertised is not being delivered?
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Old 05-03-21, 04:10 PM
  #62  
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I have seen ads which tout the reduction in rotating weight as a significant advantage. Any search I've done says this is a myth or, at best, there is a minimal advantage in specific situations. IMO this does not justify a large expenditure of money. Especially when I could, and should, lose 10 lbs.
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Old 05-03-21, 04:15 PM
  #63  
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Originally Posted by bruce19 View Post
I have seen ads which tout the reduction in rotating weight as a significant advantage.
Significant advantage in what way? By whom? Care to share some examples?
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Old 05-03-21, 04:28 PM
  #64  
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Originally Posted by WhyFi View Post
Significant advantage in what way? By whom? Care to share some examples?
Do your own research. And stop being a kochleffel.
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Old 05-03-21, 04:35 PM
  #65  
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Yes, I think that Bike Forums is the perfect venue for us to be critical of each other's statements, semantics, and intent like we are all doing peer review of each other's posts.
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Old 05-03-21, 04:43 PM
  #66  
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Originally Posted by bruce19 View Post
Do your own research. And stop being a kochleffel.
There are some riders around here that regularly participate in both National and Worlds. In the timed events it can be worth the money, since lots

Last edited by colnago62; 05-03-21 at 04:46 PM.
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Old 05-03-21, 04:48 PM
  #67  
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Originally Posted by bruce19 View Post
Do your own research. And stop being a kochleffel.
Wait - didn't you start the thread? I have never seen a manufacturer claim w/r/t rotating weight, that's why I'm curious to see those that you've come across.
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Old 05-03-21, 05:02 PM
  #68  
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FWIW, there's a bunch of discussion here about not much. Typically from what I see here on BF, cyclists get a stock bike. Don't like the wheels -- they're heavy. Lighter wheels save weight -- that's not even a question. This topic seems should be about whether a gram saved on a wheel rim is how much better than a gram saved elsewhere -- is it worth 1.5x, 2x, 3x more than another option (per gram)?

Spending money on saving weight.. whatever -- do what you want to do and buy what you want to buy. I find it an interesting premise though that there's nothing that special about a wheel gram vs another type of gram. Aero however, is a completely different topic.

Boil it down.. if you could get a 1800 gram, awesome looking blingy wheel with a cool 28mm exterior width and 45mm depth for $750, or the same described wheel, at 1400 grams, for eg. $3k, would this be something you'd consider? What's your breakeven?
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Old 05-03-21, 05:06 PM
  #69  
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Anyone who reads this thread will see a few pissing contests of no consequence, but in between is the clear point that lighter (and more aero) bikes are more fun.

And yeah, you notice rotating mass more. All the rotating mass, not just the wheels. Not so much the cranks, but consider that the whole bike rotates from side to side with the contact patches as the axis when you stand on it, so if you want your bike to feel light when you do that, start at the top - seat and bars matter like rims. Then you've got the front end rotating around the head tube; lighten all that and you'll notice that more too.

Save crank upgrades for last.
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Old 05-03-21, 05:09 PM
  #70  
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Will people notice the faster accelerating or the faster deaccelerating first?
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Old 05-03-21, 06:15 PM
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Originally Posted by Sy Reene View Post
Will people notice the faster accelerating or the faster deaccelerating first?
Before either of those, how easy it is to carry up stairs.
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Old 05-03-21, 07:13 PM
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Originally Posted by Sy Reene View Post
FWIW, there's a bunch of discussion here about not much. Typically from what I see here on BF, cyclists get a stock bike. Don't like the wheels -- they're heavy. Lighter wheels save weight -- that's not even a question. This topic seems should be about whether a gram saved on a wheel rim is how much better than a gram saved elsewhere -- is it worth 1.5x, 2x, 3x more than another option (per gram)?

Spending money on saving weight.. whatever -- do what you want to do and buy what you want to buy. I find it an interesting premise though that there's nothing that special about a wheel gram vs another type of gram. Aero however, is a completely different topic.

Boil it down.. if you could get a 1800 gram, awesome looking blingy wheel with a cool 28mm exterior width and 45mm depth for $750, or the same described wheel, at 1400 grams, for eg. $3k, would this be something you'd consider? What's your breakeven?
So why doesn't anyone ever complain their heavy aero wheels flees heavy and sluggish, but heavy stock wheels do? :-)
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Old 05-03-21, 07:45 PM
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Originally Posted by Kimmo View Post
Before either of those, how easy it is to carry up stairs.
So....Is it easier to carry up the stairs if the wheels aren't spinning?

When sprinting at speed in an important race, The aerodynamic advantage of a heavier wheel might outweigh the tiny loss in acceleration of the rotating mass.

Last edited by xroadcharlie; 05-04-21 at 02:04 AM.
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Old 05-04-21, 02:27 AM
  #74  
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Originally Posted by Racing Dan View Post
So why doesn't anyone ever complain their heavy aero wheels flees heavy and sluggish, but heavy stock wheels do? :-)
From what I have read, because the whoosh from aerodynamic wheels makes you think you are going faster. Some day, when I buy a bike with disc brakes, I will give this a try.
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Old 05-04-21, 02:49 AM
  #75  
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I've never noticed a difference in speed when switching to a light wheelset. The biggest difference is the smoothness of the ride when going from wheels with stiff straight gauge spokes and light DB spokes. Straight gauge spokes, which the majority of stock wheels come with are my pet peeve.

I did buy a Swobo single speed bike than came new with 42mm tires, cheap and heavy ones (that were too wide for the narrow rims). I switched to 23mm Vittoria open tubulars and the difference was very noticeable.
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