The Physics of Rollers

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04-23-09 | 07:02 AM

#51

Phantoj

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Quote:

Originally Posted by jccaclimber

And I stayed in a Holiday Inn a couple weeks ago. Interestingly, I feel that leaves me qualified to say that you're incorrect, especially as lean would change nearly nothing if you welded the headset strait (I'm also a year into a master's thesis on this topic).

Are you saying that Fajens and the articles on his site are incorrect? Will you provide a link to your thesis when you publish?

04-23-09 | 07:06 AM

#52

Grumpy McTrumpy

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From: Binghamton, NY

there are two types of bicycle riders

those who countersteer and know it

those who countersteer and don't think they are doing it

04-23-09 | 12:16 PM

#53

jccaclimber

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Quote:

Originally Posted by Tulex

Point being, they don't turn for balance.

They do both turn and lean for balance. It's done at a very low speed so turning mixed with leaning causes a lateral shift in your CG.

04-23-09 | 12:39 PM

#54

jccaclimber

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Quote:

Originally Posted by Phantoj

Are you saying that Fajens and the articles on his site are incorrect? Will you provide a link to your thesis when you publish?

I suppose I can link my thesis if I can remember. I believe that Fajans is correct, what I disagree with is the conclusions of AngryScientist from those papers. Comments like the one about riding a bike with a welded headset are incorrect. Saying that you can ride without hands is very different from saying that you can ride with a welded headset. Without your hands your front wheel is still rotating a bit, even if it isn't your hands causing the rotation.

If you want to get a good primer on stability find either the work of Dr. Jim Papadopoulos (Cornell) (https://ruina.tam.cornell.edu/researc..._and_links.htm) (note, VERY DENSE) or Chronicles of the Lords of the Chain Ring (Dr. William Patterson, CalPoly SLO).

Last edited by jccaclimber; 04-23-09 at 12:44 PM.

04-23-09 | 12:52 PM

#55

jack002

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From: Southwest MO

Bikes: (2) 1994 Cannondale R900, red, Silver Trek hybrid

Comments like the one about riding a bike with a welded headset are incorrect

+1. Hogwash and off topic to boot.

04-23-09 | 12:57 PM

#56

Phantoj

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Quote:

Originally Posted by jccaclimber

They do both turn and lean for balance. It's done at a very low speed so turning mixed with leaning causes a lateral shift in your CG.

I saw a bicycle tightrope rider on youtube. He had a really long 40 pound pole for balance. So I think he was mostly balancing himself and the bike with the pole.

04-23-09 | 01:00 PM

#57

Phantoj

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Quote:

Originally Posted by jccaclimber

what I disagree with is the conclusions of AngryScientist from those papers. Comments like the one about riding a bike with a welded headset are incorrect.

I think you misinterpreted his post (#11). I think he read up on Fajan's site and it changed his mind.