elcruxio

The reason why I haven't gone back to 2x from 3x is that with a 46-30 crankset you'll need a 11-46 cassette to get as low as with my 22-34-44 and 11-34 cassette. The gear jumps with a cassette like that are just nasty for road use. Frankly even 11-42 was starting to feel a bit much when I tried out 1x for touring.

Sure, I could use a 24-38 mtb double, but then I'd lose high end entirely. Maybe with a 13-speed cassette time will be ripe for me to give up the triple. But I'd much rather take a 11-speed 11-34 cassette and a GRX triple combined with hydraulic brakes. That would have so much range and so tight spacings.

rsbob 

When I first saw this thread title, I thought to myself, “Self, what an ideal set-up for a whole lot of arguing”. Wish I was wrong, again.

terrymorse 

Many moons ago seems like yesterday, that was the golden age of rec.bicycles.tech.

It's interesting to see Jobst suggest that high inertia wheels are "probably beneficial", a question that I think still has no definitive answer (the "heavy ball thrown short distance vs. light ball thrown long distance" problem, or the "big flywheel vs. small flywheel" problem).

Here's what I wrote around the same time about a sprint from standing start:

wolfchild

Boggles my mind how people who don't even race for a living will obsess about few grams of weight.

3alarmer

...and, once again, you are taking a specific case, where the mass of two wheel rims differs insignificantly, to ague that weight on the rotating mass is effectively equivalent to that on the frame. I can't really state it any more clearly than that. My guess is that you've never done the switch suggested by another poster, upthread. But it's only a guess. I don't really know you, or how and what you ride. I ride mostly older stuff, so it's easier for me to tell the difference.

...what is my misunderstanding, exactly ? You have taken a very specific case, and run with it.

...if you think I'm offended by any of this, you don't understand anything about me.

...are you, are are you not, arguing from the specific to the general here ? If you really believed in all these "flywheel" arguments, you'd be riding a much significantly heavier set of wheels. Maybe it's because I'm old and out of shape, but I find myself applying force to the pedals on my bicycle all the time, and it's not just to maintain a constant speed. I can tell because my legs get tired. If there's a "myth" here, it's that the average bike rider, on the average bicycle ride, attains a certain maximum speed, levels off, and then proceeds apace. That's not in keeping with what I encounter in my own private universe.

MikeWMass

Two comments:
1. I like my triple crank because I can use the big ring on mostly flat terrain and the middle on hilly terrain, as there is enough overlap, and use the granny for truly steep stuff. Also it shifts better than the double ever did.

2. Regarding gyroscopic force, if you pull back on the left handlebar, the bike will lean right. It is less necessary to do this on a bicycle than on a several hundred pound motorcycle, but it does work. This is one case where gyroscopic forces can be significant.

PeteHski

No I wouldn't be riding a much heavier set of wheels. I do a lot of climbing, so the total mass does matter. What doesn't matter is the rotational inertia. I can see you are just going to make this harder than it already is and I don't really see your contribution helping anyone. Your rate of acceleration is very low as you are plodding around and hence inertial forces are also very low. Clever people have run the calculations to prove it. You can disagree with their results if you like, you wouldn't be the first.

squirtdad

[QUOTE=wolfchild;22803992]Myth # 1 Singlespeed bikes are only good for very short distances on flat terrain



Myth # 4 Drop bars are more comfortable than riser bars or flat bars.

/QUOTE]

in my case this not a myth..... flat bars give me a lot of pain

squirtdad

1) Steel if heavier than aluminum or carbon

2) flat bars are more comfortable than drop bars or north style bars

HTupolev

One of my bikes has two wheelsets that both use box-section clincher rims, but which differ by 600g, with much of the difference in the spokes and rims. The heavier set was dirt cheap, I bought it to get the bike up and running. The lighter wheelset I built later. My typical tire setup on that bike is 2.1" Rene Herse EL slicks with latex tubes, and I've used it on both wheelsets.

It's very easy to feel the difference between the two wheelsets.
But.
What makes it easy to feel is the gyroscopic differences with respect to bike lean and the steering axis. The choice of wheelset causes the bike to steer differently in hard turns, and respond differently to being thrown around out of the saddle.

I don't think I'm able to directly feel a difference between the wheelsets in terms of how much acceleration I get for a given effort.

Gresp15C

Myths that I've heard from friends and colleagues:

1. A modern bike is too complicated for a cyclist to maintain themselves

2. A bike needs to be taken to the shop for a "tune up" every year

3. If a used bike is more than 3 years old, it will need to have everything replaced: Tires, brakes, cables, everything

4. A bike should never get wet, and if it does, it should be completely disassembled and re-lubricated

5. You need to be a "die hard" to ride during the winter

6. My time is too valuable to patch a tube

7. Any bike with rim brakes is a death trap

8. Weight / quality doesn't matter

tomato coupe

It actually doesn't matter. Even if you somehow managed to accelerate 100% of the time, the additional rotating mass would be of little consequence.

3alarmer

...break out the steel wheels.

3alarmer

...I was hoping to avoid pointing out the obvious strawman argument, with which you kicked off this exchange. Apparently, that's impossible.

...somewhere, I remember you or someone else stating the myth as "an ounce on the wheels is worth a pound on the frame." I had never heard it put that way, but I have heard plenty of times that weight saved on the wheels is worth about twice that on the frame. With which you seem to agree:

...which is fine, so long as you keep the difference quantities in your calculation low:

What makes these exchanges hard is not my ignorance of physics. The physics involved is pretty basic stuff. What makes it hard is responses like these:

In a very real sense, this reminds me of arguing with a flat earther. They usually begin with a strawman, like, "If the earth is round, why does it look flat when I'm driving on the freeway in Iowa?" Then they will continue, by arguing from the specific to the general. "We have some pretty tall buildings here in Des Moines, and I've looked out from the 16th floor of one. I still can't see any curvature of the earth." I know it's difficult, but I'm asking you to look at this argument from the perspective of someone looking through a telescope, rather than a microscope.

And, invariably, those guys all quote "the science", as being on their side. Anyhow, nice talking with you. Beautiful day here, so I went for a ride.

tomato coupe

Actually, it is.

PeteHski

The problem here is that you appear to understand the basic physics, but not how to actually apply it. It's easy to say that rotating mass is worth approximately twice that on the frame from the MOI equation, but that doubling factor only applies during acceleration and what the calculations show is that those accelerations are both minimal and mostly self-cancelling. So in reality it's not really worth anything. But maybe all those scientists and engineers are wrong. Unlikely, but if you can show your own calculations that would be great.

The other problem is trying to wade through all the BS speak in your posts to actually get to your point. I know it's your style, but it's not really helping here.

PeteHski

You see this shows your lack of understanding (or ignorance if being less polite). Mass is important on a bicycle. It's just not any more or less important on the wheels.

HTupolev

This is an inaccurate way of describing it that actually makes it sound more significant than it is. It's not that it applies during acceleration, it's that it applies with respect to acceleration. So for example, if you're accelerating while climbing a hill, the doubling factor does not apply to gravitational resistance just because you happen to be accelerating.

Atlas Shrugged

But that is all these forums have become. It is the last holdout for the Luddite contingent of sport cyclists. Bring up any reasonable topic and the usual 1970’s know it all respond with a ridiculous non answer or why friction shifting and tubulars were peak cycling etc. I have learned to ignore what is happening over in C&V but it frustratingly moves over to the other sub forums.

Camilo

It's just a fun part of the hobby. Nothing more, nothing less. I built up a <16 lpound (15.1 actually) bike just to see if I could do it fairly economically. Measuring even handlebar tape, tubes, tires of course, chain, every hardware. Every 1/2 ounce counts. But no delusions that it makes me faster.... it is just fun.

PeteHski

I was thinking that was obvious since we were discussing acceleration. But I suppose it is a useful clarification for those who might not understand the difference.

Camilo

It's more that people just like to argue ad-nauseum and aren't embarrassed by it. I'm often impressed by the knowledge brought into the arguments, but have little actual understanding as to who is correct in the shifting nuances (trivial?) of the debates.

PeteHski

That's the problem with public forums. Usually it's the experts who are correct.

MoAlpha

Ad nauseam with an “a.” Carry on.

SpeedyBlueBiker

"Entry level bikes are just a gateway to more expensive bikes." Before you know it, you will have a garage full of bikes with each one costing a little more than the one before it.