The skeptic will say: "It may well be true that this system of equations is reasonable from a logical standpoint. But this does not prove that it corresponds to nature." You are right, dear skeptic. Experience alone can decide on truth. ... Pure logical thinking cannot yield us any knowledge of the empirical world: all knowledge of reality starts from experience and ends in it.
(Albert Einstein, 1954)

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Indoor Triathlete - I thought I was right, until I realized I was wrong.

4/10 on hostility.

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Indoor Triathlete - I thought I was right, until I realized I was wrong.

Cute, but Einstein did the math to back up his ideas. You haven't.

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Swimming Workout of the Day:

Favourite Swim Sets:

2020 National Masters Champion - M50-54 - 50m Butterfly

Well if we know everything there is to know, why bother with thinking and just do as we are told?

The eternal mystery of the world is its comprehensibility. (Albert Einstein)

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Indoor Triathlete - I thought I was right, until I realized I was wrong.

You are depressing me.
With so much easily searchable information at your disposal, you find quotes you think support your ignorance based stance, instead of trying to use it to understand why your approach is not reasonable.

The 2nd law is dammit!

I shall retire.

Okay, you posted this while I wrote the last one so I get another go!

Who said we know everything there is to know?
Who's just believing what they're told?

We know a lot, we don't know a hell of a lot. You're picking things we understand and saying "Gosh if only mankind could figure this out". Can you imagine how silly that sounds to those who actually understand the concepts and have told you as much?
Competence in any field is largely about gaining an understanding of what you do and do not know. You have demonstrated that you don't know what you don't know. I don't know everything, to claim anything of the sort would be absurd. I do hope to have some idea of what I can discuss with some confidence that I'm describing reality. There's a difference between having read something and regurgitated it, and having actually understood it, tested it, and accepted it.

You are abusing all those quotes. I do not think they mean what you think they mean! ;)

You would be surprised.

Just like your angular momentum theory, your theory about abusive youth and gentle elders has some holes in it.

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Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Note that the above is exactly the same as what Al_1 said. Or at least it's meant to convey the same message.

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Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

7.5/10 passive aggressive trolling post.

Having no understanding of the purpose of asking about my age (why would that matter in this discussion?), I didn't deign to answer. I probably have underwear older than IT.

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"Go yell at an M&M"

IT has this idea that young people are abusive trolls, and that only older people (I think he's near or over 70; he's older than waterboy, that's for sure) understand the art of civil discussion.

I think he's wrong both ways.

(He's also the only person here who thinks waterboy is not been given fair treatment here)

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Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Someone thinks waterboy is the victim rather than the mass offender?!
Is this because of a shared belief that reasoning can be conducted by vague assertion alone without any need for consistency or logic?

He's not a victim, at all. He wants to be "attacked". Otherwise, how else to explain the constant inflammatory statements and passive aggressiveness?

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Swimming Workout of the Day:

Favourite Swim Sets:

2020 National Masters Champion - M50-54 - 50m Butterfly

Oh, I agree completely. It's a little attention seeking game he plays.

Have you read the post on Bike Tech review where I measure the coefficient of rolling resistance for the water inflation? It does increase the rolling resistance but not by much. Could not detect any benefit even controlling for the the increased rolling resistance in field. I did the study as my senior thesis as and undergraduate. I also have experimented with alcohol and oil inflation. Attached is my report of the study I did my senior year in college.


http://biketechreview.com/index.php/forum/1-general-discussion/26943-crr-of-water-inflated-tires



Note: I realized some the error bars in this draft of the report had an error, on the Bike Tech review post they are correct and I re uploaded the file so they are correct.
Also note that in the attached report I say Moser set and hour world record on a high inertia wheel. While it is true his ride on his large wheel was a notable performance, from my current understanding it did not break the world record at the time.

I try to make up for the difference by having extreme interests in high intertia wheels. Although I don't ride any more because I am to busy spending time with my wife , doing Density Functional Theory simulations of solid state electrolyte materials, and plus I have an injury preventing me from racing any more. I personally have modified spooked wheels into a 8 and 12 pound disk named the "Chunky Churner" and the "Air Hammer". My dream is to have the most absurdly heavy bike wheels machined for me, like at least 20kilo a piece. They will by named "Rampager Heavy Elites".

You sound like a customer for my disc wheel machined out of solid depleted uranium. 827kg. I call it "The Nuclear Option".

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Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
Instagram • Facebook

Now that would be a set of wheels. It would be a curious thing to find out how they rode. Its hard for me to imagine what it would be like. On another note is seems you are a machinist of sorts. What do you think it would cost to have a set of very heavy, say iron wheels machined? Maybe like a deep iron rim front and rear with the rear wheel covered to make it a disk.

No, its the "Stalingrad" HED rear Disc April Fools joke IRL

http://www.velonews.com/...-from-steve-hed_9673

You might find it funny that I emailed HED and actually asked how much it would cost to make them "the Stalingrads". At the time if it was less than several thousand I would have bought them. Needless to say they didn't respond. I find it would be interesting as and oddity/novelty to investigate the extremes of bicycle physics.

You don't think gyroscopic effects might become a bit dangerous if you went for really heavy rims? And for what sensible benefit?

In this case no benefit, just for pure amusement and theoretical curiosities about the effects on the dynamics of the bike rider system.

Fair enough!
But if you go above a few kg per rim it may become wise to take precautions against the possibility of crashes.

IT would be considerably cheaper, easier and more adjustable to add weights on the spokes adjacent to the rim rather than machining a bespoke heavy rim.
If I wanted to know how a bike would handle with a considerably heavier wheels I'd probably do the following:

1. Get a cheap set of sturdy touring wheels - say 36 spokes?
2. Make up 72 identical weights that can be clamped to the spokes just inboard of the rim, making sure they don't protrude far enough to risk hitting the brakes, fork, chainstays or anything else. Say 120g each?
3. Fit a proportion of the weights, say 3, 4 or 6 of them to each wheel
4. Ensure the weights are all completely secure and they are evenly distributed around the wheel
5. Check the wheel remains in balance
6. Test
7. Repeat steps 3 to 6 with additional weights each time until you are at full capacity of 36 weights per wheel or until handling or other problems are envisaged or experienced

With 36 spokes and 120g per spoke, that's 4.32kg added to each wheel if you can add them all. So if the wheel is already say 1.2kg, you'll be at about 5.5kg per wheel. That's fairly substantial. I don't know if it's what you had in mind or if you wanted to go further. Obviously with the weights a little inboard of the rim there will be a bit less moment of inertia than you would have for the same mass at a larger radius but it gives you a potential way to get much of the effect with a more practical, cost effective and scalable experiment.
Disclaimer: I am not recommending you should actually do the above. If you're considering it, I'd certainly say you must do your own risk assessment and determine whether or not it can be done safely. For example, can the bike frame, wheel rim, spokes, brakes, etc deal with the additional loads without distorting or failing? Likewise, can you make the conditions for testing (protective clothing, helmet, environment, etc) safe enough that poor handling won't create a significant safety risk?
Be careful! If it were me, I'd certainly be very hesitant to ride such a contraption at speed.

Hmmm.... it depends a lot on how you would need to structure the wheel - it *might* be true that when riding in a straight line that normal spokes would be fine, but I can imagine that just picking up the bike, braking, inertial effects in turns or gyroscopic effects could require much stronger spokes, so it probably needs to be shaped more like a HED H3. It would probably be most economical to cast that part instead of machine it from a massive block of iron (which you might need cast just to get it in the right shape first, then waste most of the material). If you wanted to make just one, I would suggest 3-D printing the molds and cores out of sand, and then sand casting. Then you'd have to do some finish machining. No idea what you'd have to do for hubs/bearings so we'll just assume that happens magically for free. It's not a super-complicated shape and probably just regular gray iron would be fine. I'd guess you could get that done at $15k-$20k per wheel. That is just a total guess, based on a little experience. Compacted graphite iron engine blocks have cost me as much as $100k each so... the range is wide.

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Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
Instagram • Facebook

The discussion on wheels is so off the track of what I wanted to suggest as OP.

The rotation of the arms/legs impacts swimming, cycling and running. It's not just about the downbeat but the upbeat as well.

My suggestion is that leg lift helps one's hip rotation and push off while running.

The throw forward of the arm while swimming helps one's rotation and pull.

The right cycling cadence and leg follow through is more like the wheel discussion and more focus on that will give you more gains than adding weights to wheels.

In regards to crank length... In effect we are riding a single gear until we shift gears of course. A shorter crank helps the rider's legs complete the circle (respond) in a shorter period of time compared to a longer crank making that longer circle. I can definitely respond better to another rider's acceleration with shorter cranks which involves the legs over a shorter distance than with the longer cranks.

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Indoor Triathlete - I thought I was right, until I realized I was wrong.