Component friction testing

Discuss light weight issues concerning road bikes & parts.
bm0p700f
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by bm0p700f

Like all good research is needs to verified independently. It is a starting point though.

ticou
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by ticou

WMW wrote:
ticou wrote:I pay for goods not information.


This sort of information is important for deciding what goods to buy. And it's relatively cheap information. And it cost a lot of money and time to obtain.

If you feel that all information should be free, then that means you are fine with being limited to information that costs little or nothing to obtain, or some other party profits from dispensing... ie they have an ulterior motive for making it available, and it is usually tied to advertising. That isn't a very good way of finding out the truth.



A fair point, but I use my 30 years experience on bikes, the valued experience of top flight independent lbs's, the track record of a company,multiple owners opinions, and only then did my aesthetic and gut feeling go for Campy. I do not rely on advertising, ever. A youtube vid might help, but that's the cherry on the top.

by Weenie


fdegrove
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by fdegrove

Hi,

only then did my aesthetic and gut feeling go for Campy.


IOW a perfectly subjective choice.
Whilst I agree that Campa's stuff is leading edge as far as combatting friction goes in currently available grupos and wheels, I must add that there's still quite a margin for improvement left.

Ciao, ;)
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HakeemT
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by HakeemT

fdegrove, earlier in this thread you mentioned optimising your bikes for 'as low as possible friction'. Any pointers you could give the rest of us?

Not necessarily looking for something along the lines of this component friction testing study, but more around the type of 'adjustments' you would normally make to hubs (e.g. tighten/loosen cones), freewheels (e.g. different grease), any specifics around chain lube etc.
You obviously have a lot of experience so would love to hear your thoughts.

I know you've written posts along these lines before, but I find it difficult finding the gems. It could also tie in nicely with Tinea's road forum index?

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WMW
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by WMW

fdegrove wrote:Whilst I agree that Campa's stuff is leading edge as far as combatting friction goes in currently available grupos and wheels


Have you read the report? I think it might disagree with you...

Much of the friction on the bike is simply impossible for a rider to discern. It's too small... people can't even detect a 10W increase in drag from the tires, let alone 1W in the bearings.
formerly rruff...

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tommasini
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by tommasini

bikedoc wrote:does anyone really worry about how much energy a jockey wheel is costing them??


after watching this video and comparing to your own stock pulleys you tell us - is there a potential difference and also could the mental encouragement gained also help your performance? http://www.youtube.com/watch?v=KiXH7HDRPKYAfter" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;"

I've added up a number of individual 3 - 4 or more watts saved (claimed) from a few focused aero improvements, riding fine tubbies, and bearing improvements (w/Campy CULT). While each one incrementally is a pretty small gain, the real life collective gain from all of them is VERY noticeable to me - having 2 very similar bikes that only differ in the areas just noted. Plus knowing what I've done I take on an added pressure to perform to the level of my equipment - no let downs.......so collectively reducing watts and gaining the "encouragement" from the improvements I've found it to be quite frankly....addicting....... :beerchug:

And here is another example - again training, tactics, personnal genics, etc, etc will be most important, but incremental gains in other places can add up. http://www.youtube.com/watch?v=IpLbLJhe ... re=related
Last edited by tommasini on Fri Nov 09, 2012 1:50 am, edited 2 times in total.

ticou
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by ticou

There is no such thing as perfection in bikes, but when you get subjective and objective smoothy woothies, I'm a happy camper with Chorus.

fdegrove
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by fdegrove

Hi,

Much of the friction on the bike is simply impossible for a rider to discern. It's too small... people can't even detect a 10W increase in drag from the tires, let alone 1W in the bearings.


Why would it matter when someone can discern the difference or not? Surely if it can be measured it must be there?
1W here, another Watt there....At the end of the day it all adds up and that's what it's all about I would think....

Ciao, ;)
Being a snob is an expensive hobby.

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WMW
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by WMW

I think you are misunderstanding me... you claim to have "perfected" your drivetrain losses, without test data. Since the differences are too small to be discerned by the rider, how could you know this is the case? Spinning parts in your hand certainly won't do it... it has to be under load.
formerly rruff...

sawyer
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by sawyer

on the loaded vs. unloaded point ... is there any convincing research that supports that for bicycle components - i.e. that there is little or no positive correlation, or even a negative correlation - god help us - between friction when unloaded and friction when loaded in a drivetrain/wheels?
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WMW
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by WMW

Unloaded friction is going to be mostly seals and grease so long as the bearings are properly adjusted. This is a big deal with some new and recently overhauled parts, since it takes time for grease and seals to "break-in". If a new part spins very easily, it probably has crappy seals and light grease... and will need to be overhauled more frequently, while providing very little resistance benefit.

Under loads, the actual bearing friction comes into play along with any issues due to bending and misalignment.
formerly rruff...

fdegrove
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by fdegrove

Hi,

WMW wrote:I think you are misunderstanding me... you claim to have "perfected" your drivetrain losses, without test data. Since the differences are too small to be discerned by the rider, how could you know this is the case? Spinning parts in your hand certainly won't do it... it has to be under load.


That does not mean there is no test data. Data taken from one set up can be ported to the next one and so on.
It isn't exactly rocket science either.

If a new part spins very easily, it probably has crappy seals and light grease... and will need to be overhauled more frequently, while providing very little resistance benefit.


Probably always the case with industrial bearings: when it spins suspiciously easy it more often than not tells you it is of the low tolerance, low quality metal retainer type.

The problem with these industrial bearings is that no matter how good they are, none of them are designed with our kind of use in mind.
You occasionally come across some that have been made to order or carefully selected for our kind of application but I bet that most guys in the industry just can't be bothered.
Which is why these measurements are so important. If it clearly shows that better bearings/lubricants/seals etc. are wortwhile we'll at long last have some leverage.

@Sawyer: You can safely say that there is no correlation.

Ciao, ;)
Last edited by fdegrove on Fri Nov 09, 2012 2:17 am, edited 1 time in total.
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Tinea Pedis
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by Tinea Pedis

Looks like James lurks ;)

by Weenie


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by VNTech

Jason (Friction Facts Man) is based in Boulder, so James and I are both on this. :) He's doing some exclusive testing for us, for an upcoming issue. In fact, James mentions it...
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