MKahrl

What I want to know is if rotating mass makes a difference on bikes hanging from trunk racks with one wheel spinning while the car speeds down the highway. Do micro-accelerations affect gas mileage?

Kimmo 

You can fit 1279 angels onto the head of a pin

seypat

The spinning added mass is what causes the handlebars to spin around a put a scratch in your paint.

walnutz

This is the only thing that really matters in this thread so far

drsmoooth

Exactly!!

Seattle Forrest

​​​​​​What does your eating too much have to do with wheel makers advertising and not delivering? These are two unrelated concepts.

seypat

Pizzas kinda look like wheelsets. You can get a pizza delivered to your house by the pizza maker. The wheel companies use a third party for shipping however, and it usually cost you a fee to get them there. That's the only spin I can put on it. That and don't spin the pizza or you could lose the mass off of it.

tomato coupe

That was in the 12 speed era. You can fit more now.

Seattle Forrest

The plot thickens...

seypat

Awesome! You need to post that in the "luxury upgrades" thread along with a link for where to get it.

tomato coupe

Thru axle? Seriously?

Bearhawker

I suppose I could try, for the sake of science and all.

Not sure the wife would be on board, but... science. Hard to argue against science.

bruce19

Let's start with you admitting that you misrepresented my original post.

Seattle Forrest

I went back and had a look, and you're right it's your third post I was responding to not your first one. Nonetheless, people are allowed to have wheels they like even if you want to lose ten pounds, and I still don't see the connection there. I can see the bit about "willing to be convinced otherwise" was pulling our legs though.

bruce19

First....thank you for the clarification.

bruce19

As to this statement that I made....."My take away thus far is that there has been a lot of money spent for not much gain. I am willing to be convinced otherwise but so far that's where I am." What I was trying to say is that I see a lot of money being spent on wheels because lighter wheels reduce rotational weight. That supposedly has a major benefit. However,when I do a search about rotational weight, I get results that say that this "attribute" is largely a myth. If there is some science that says that rotational weight is what we have been told it is, I would like to see it. And, thus, I am willing to be convinced. This ignores the fact that some people "feel" a difference. I have no problem with that. We all spend our money on what we like. I'm just trying to sort out the objective science of it all.

asgelle

https://www.recumbents.com/wisil/Mart...%20cycling.pdf
Wheel Performance

bruce19

My comment about losing weight is meant to address the issue of rotational weight vs weight generally. If rotational weight's importance is basically inconsequential, that doesn't mean that a lighter wheel weight is unimportant. It only means that it's the reduction in overall weight that may have a significant impact. In that case, if I lose 10 lbs the overall weight of bike and rider would be reduced by 10 lbs without me spending $2-3K for a wheel set that might reduce the weight of bike and rider by a lb or so. Anecdotally, last year I lost almost 15 lbs and my climbing was so much easier and better. My bike's weight of 17+ lbs as ridden did not change. The point I was trying to make is that it is more cost effective for me to lose 10 lbs than to spend a lot of money to lose a lb of bike/rider weight. I was speaking for myself and not trying to say that other people should avoid whatever wheels they want.

bruce19

This is weird. I clicked on the link and Firefox said there was a "potential security risk" associated with that site. I have no idea why
l.

asgelle

try https://collections.lib.utah.edu/dl_...0d77868437.pdf

Kimmo 

Anyone can feel the difference, no scare quotes required. It's just that the difference that's felt is not a free lunch, which is often neglected.

aclinjury

I see that you want to look at this from a value judgement angle. That's fair enough.

But I can tell that you have never ridden or jumped a bmx bike vs a downhill bike either.. Bmx bike spins and gyrates differently compared to the downhill bike, and it not just because of bike size either. Rotating weight. Forget bmx, just take a road bike and put some 50mm deep wheels and sprint, now do it with 80mm wheels. Tell me if you don't sprint quicker in the 50mm. Climbing is just a series of mini accleration. Does it matter now? up to the rider to judge, but if rider cares about performance, then it matters.

asgelle

There is no way to say a priori which wheels will accelerate faster. There is the tradeoff between extra weight/moment of inertia and aero benefit. I am virtually certain that if the 50 mm wheels are faster accelerating than the deeper ones despite their aero penalty, it is almost certainly due to the effect of less total mass and not the lower moment of inertia which is an order of magnitude less significant. Wheel Performance

terrymorse 

Not, it isn't. Climbing is all about power-to-weight ratio.

Atlas Shrugged

Rest assured if one rider has 3.5 w/kg and another has 3 w/kg it won't matter who has the lighter wheels 3.5 w/kg will be faster. If both riders had the same w/kg saying the rider with lighter wheels would be noticeably faster is doubtful at best.