livedarklions

​​​​​​He liked it because he got the joke. Apparently it went over your head. I'm in the discussion now, so what? I'm having fun with it. Unlike you, I haven't insulted other people for engaging in it.

livedarklions

My point was that AI gives you the answer you want based on how you ask the question. You were the one who actually thought you were proving something by posting AI generated answers, but this post proves my point--AI is an absurd tool to cite as authority.

You do understand that all it's doing is drawing ideas from unspecified sources. It lacks the capacity to determine whether the information is actually reliable or not, or making a judgment like if something is significant or not.

livedarklions

​AI 100%. Was this supposed to be a trap?

wolfchild

I just noticed that all the posters who say that weight makes no difference are the the very ones who have spend many thousand of dollars on the lightest bikes and wheelsets that they could find. .Some of them are riding $ 4000 ultralight wheelsets without valve stem nuts and caps to save even more weight and now they're arguing that wheel weight makes no difference...LOL

PeteHski

Okay, just for fun I made a very simple spreadsheet to calculate average power required to accelerate a bike from a standstill to a given speed.

So my simple bike model:-

Static mass m = 85 kg
Rotating Mass (wheels and tyres) mw = 3 kg

Initial speed u = 0
Final speed v = 11 m/s (40 kph)
Acceleration a = 0.75 m/s/s
Time taken t = 14.7 s

Kinetic Energy of static mass = 0.5 x m x v^2 = 5143J
Kinetic Energy of rotating mass = m x v^2 = 363J (Simplification with 100% of rotating mass at the tyre radius)
Kinetic Energy total = 5506J

Av Power total = KE/t = 375W
Av Power for total rotating mass = 25W (6.67% of total power)

If I saved 1 kg from the rotating mass (i.e. 33% - a very large and likely very expensive saving):-

KE static = 5143J
KE rotating = 242J
KE total = 5385J

Av Power total = 367W - saving of 8.3W (2.2%) over baseline:-

If I saved 1 kg from the static mass (a free trip to the toilet or a couple of weeks not eating junk food):-

KE static = 5082J
KE rotating = 363J
KE total = 5445J

Av Power total = 371 W - saving of 4.1W (1.1%) over baseline

So with my simplified model (worst case rotating mass ENTIRELY at the tyre outer radius), I save an absolute maximum of 4W (1 kg rotating vs 1 kg static mass) over an acceleration from 0-40 kph at 375W. Also consider that this calculation doesn't include additional power required to overcome air resistance or rolling resistance. It is only the power required to accelerate the mass.

Notes:

1. This is all my own working out using the appropriate equations with real world parameter values. So no 13 kg wheels made out of solid aluminium.
2. The simplifications and values are intended to maximise the effect of rotational inertia i.e. high acceleration, large mass saving and maximised wheel MOI.

PeteHski

We are not arguing that weight makes no difference. We arguing that wheel weight is no more or less important than frame weight. So pay attention.

smd4

What? My bike is a high-performance racing bike, not a touring bike or hybrid or Lincoln Town car. Why wouldn't I want that kind of road feedback from a racing bike tire?

Search me. Although I'm pretty certain the mechanics aren't the ones making the choices.

Maelochs

I love it when two (or more) people think they are debating when one or both parties is/are deliberately misinterpreting everything the other says in order to "win" the debate.

One cannot "win" a debate if one is not debating the same ideas as the "opponent." And absent honesty, all we have is nonsense.

Jeff Neese

Well done. I didn't double-check anything but I'll accept it at face value. Do you take this to mean that the differences that cyclists have experienced since the biginning of time are all due to gyroscopic effects, or that it's all the placebo effect?

Dan Burkhart 

Oh yeah, this is epic!

FBinNY 

I'm used to apples and oranges arguments on BF.

But this is more like a fruit salad.

PeteHski

Double check it if you like although, based on your own previous attempt, I seriously doubt you have the skill set required. But it is a very simple model to understand and gives some idea of the parameters involved and their relative importance.

What you mean the "huge" differences in acceleration, braking and handling? The ones that you "feel" and some other people don't?

It sounds like you own several wheel sets that you swap on the same bike. Tell me a bit more about them i.e. make, model, weight, hubs and tyres fitted. Then we can calculate how they may affect your acceleration.

Or you can just keep your head in the sand.

livedarklions

If there's a more dishonest way to ask that question, I'll be damned if I know what it is.

Jeff Neese

Sure. I'll keep it simple and we can just compare tires. The rims also have some minimal difference in weight but let's discount that for this discussion.

One set of wheels have Schwalbe Little Big Bens, coming in at 590 grams. Another set has GP5000 25C, which are 220 grams. I can use both sets of wheels on three different bikes. To say the difference is like night and day would be an understatement. Some people in this forum get it and they have already explained similar differences with their own wheels. Those are two of mine.

tomato coupe

Wow, you couldn’t pick two more dissimilar tires. It’s like saying “my 25 lb. full suspension mountain bike feels different than my 20 lb. Road bike - I think it’s because of the weight difference.”

Jeff Neese

In this case the only thing that is changing are the wheels. Same bike. Night and day difference in the way the bike handles and the dynamics of riding - almost like a completely different bike. Again, only changing the wheels.

tomato coupe

You’re changing between very different tires. Maybe you haven’t heard, but tires are a huge contributing factor to the “feel” of a bike. Are you really that clueless?

livedarklions

Just FYI, I started a thread in User Suggestions asking for a new rule banning bot-generated posts. https://www.bikeforums.net/forum-sug...ted-posts.html

I linked this thread in my OP as an exhibit. I've been clowning around in this thread with the AI just to make the point as to how worthless it is as a substantive source, but have stumbled on just how easy it would be to overrun any given thread with a bunch of vapid content that sorta kinda is on-topic.

I think the threat of this and other forums degenerating into bot vs. bot debates is a real spam-like possibility. Agree or disagree, I invite others to comment on my thread in the other forum.

livedarklions

Has he crossed the "he has to be a Poe" line yet?

Jeff Neese

There are differences, although to a lesser degree, between my 28C Paselas and the 32C Paselas. Not much, but it's definitely there. Are you going to talk about contact patch next?

Adjectives I would use might include "sportier", "more nimble", "quicker", and simply "more fun". The downside is usually ride quality of course, since reducing weight almost always involves skinnier tires. I do feel more stable during fast descents on heavier tires. Others may have their own way to describe the differences, and in fact they have.

tomato coupe

So, you’ve also missed the multitude of threads about how much tire width changes the feel of a bike? At this point, I find it difficult resisting the urge to make a comment that could get me banned.

3alarmer 

livedarklions

So wait, are you suggesting that because you see a smaller difference between the 28mm and 32mm tires than you do between the 25mm and the 38mm tires, that suggests that the reason for the difference is tire weight? What the hell?

Even if you could quantify the "not much" handling differences between the otherwise same 28mm and 32mm tires, you still wouldn't be able to ascribe those differences to weight as you didn't keep the width constant.

3alarmer 

...yet, of all the AI generated posts you put up, this was the only one he "liked". Curiouser and curiouser.

...

tomato coupe

You really are a dishonest person. I put a like on 3 of his “AI” posts because I thought they were all humorous.