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PostPosted: Wed Jun 12, 2013 10:11 am 
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I'm not asking for results and will go buy it but does the pedal report include all pedals? I.E. I ride Time Xpresso 12, are they on there?

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PostPosted: Wed Jun 12, 2013 12:55 pm 
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Juanmoretime wrote:
I'm not asking for results and will go buy it but does the pedal report include all pedals? I.E. I ride Time Xpresso 12, are they on there?


Each report say's what is tested before you purchase.

Pedals tested are:

Crank Bros Eggbeater 3
Look Keo Blade Carbon
Mavic Race SL Ti
Shimano Ultregra
Speedplay Zero SS
Time I-Clic 2 Carbon


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Posted: Wed Jun 12, 2013 12:55 pm 


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PostPosted: Wed Jun 12, 2013 1:45 pm 
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deermatt wrote:
. I more so wanted to see it to pass the time, and i like facts, but cant see it being worth buying.


It's freakin' $5 for a report, $10 for the full suite: hopefully the time you spend reading it is worth more than that, or you're paid less than minimum.

And 2 watts is like saving 500 grams or more off your bike.

Trust me: it's worth the money.

I've got to get the pedal report.

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PostPosted: Wed Jun 12, 2013 2:59 pm 
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Clearly nothing is free the cost of the parts will cost :-). With the cost of the info being insignificant relatively speaking I love love to hear the bottom line results because that is where it counts. Start posting some results with clear measurable comparisons of individual performance then we can talks about it.
Loose 5 lb. and improve the way you train and that translates in to a lot more and it will be free.
Bring it! :twisted:

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PostPosted: Wed Jun 12, 2013 4:33 pm 
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The only problem is that he doesn't test parts after they're worn and seen the same conditions. When I wanted pulleys I got the pulley report to replace my worn SR jockey wheels. It won't give anything away, but SR weren't the best new, however, my friend's Hawk Racing pulleys spin a lot less smooth after use and the KCNC pulleys that were ranked better than SR are junk after a few months. So in the end I went SR knowing that they last, but the report doesn't capture that kind of stuff.

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PostPosted: Wed Jun 12, 2013 5:17 pm 
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Wow pulley jockey wheels wear?
Never replaced one before.

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PostPosted: Thu Jun 13, 2013 7:28 pm 
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KWalker wrote:
I bought them a few weeks ago. Altogether and with all the RR data out there it will hopefully help a client of mine save around 20-24w on his TT bike (pulleys, chain, tires, and glue job).


Open question here, as I'm just curious... I've always been told that at speed you spend about 90% of your effort on wind resistance (even a professor in a sports physics class at the university told me so when we talked about aerodynamics in sports), and then we talked about some 35km/h so fairly slow...

Let's just for the sake of argument say you still loose 90% to wind resistance at 45 km/h, some 450 watts or so, right? ...can you actually shave 24 watts out of those 45 watts (your 10% non-wind resistance)? It sounds so unlikely that you could easily cut all mechanical resistance in half?

Please enlighten me?

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PostPosted: Thu Jun 13, 2013 9:39 pm 
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On the wear side, don't confuse wear with contamination. Dirty pulleys have more resistance. FrictionFacts uses an ultrasonic degreasing step before each test, typically followed by a "wear-in" cycle which helps reduce friction from the initial installation, so the tests tend to be under fairly optimal conditions. One take-away message is more important than equipment choice is equipment condition. A pro rider would have his drivetrain completely cleaned and lubed before any event of any importance.

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PostPosted: Thu Jun 13, 2013 11:55 pm 
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DMF wrote:
KWalker wrote:
I bought them a few weeks ago. Altogether and with all the RR data out there it will hopefully help a client of mine save around 20-24w on his TT bike (pulleys, chain, tires, and glue job).


Open question here, as I'm just curious... I've always been told that at speed you spend about 90% of your effort on wind resistance (even a professor in a sports physics class at the university told me so when we talked about aerodynamics in sports), and then we talked about some 35km/h so fairly slow...

Let's just for the sake of argument say you still loose 90% to wind resistance at 45 km/h, some 450 watts or so, right? ...can you actually shave 24 watts out of those 45 watts (your 10% non-wind resistance)? It sounds so unlikely that you could easily cut all mechanical resistance in half?

Please enlighten me?


I cannot answer your question in the way you posed it but his position has been optimized using roll down tests as best we can.

RR data shows that a switch from his old tires to new tires should net around 12-15w depending on how good his glue job is.

The new chain should save another 6w.

Properly cleaned and lubricated spindles another 1-2w.

Jockey wheels we're unsure of.

So if he had not optimized those things he'd have that many more lost w in terms of friction and RR. Also changed his helmet, which helped in the roll down tests. If we want to believe Castelli his new skin suit should add something I've not included in these calculations.

So if you add it up for a pro:

Oversized pulleys: 2.4w
Optimized chain: 6w
Ceramic BB: 2w
Proper width tires with appropriate glue job: 12w

Simply covering these bases nets them 22.4w over competitors that do not do these things. It might not be this much in practice, but it makes sense as to why they bolt on Berner derailleurs on special days, re glue tires and match them to the rim width, and pursue such small gains.

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PostPosted: Fri Jun 14, 2013 6:35 am 
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Yes ofcourse I too believe in optimizing everything that can be optimized, it was just the numbers that seemed so out of line when put into context?

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PostPosted: Wed Jun 19, 2013 8:56 pm 
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Just adding this which references pulley size.

The difference from best (15-tooth) to worst (10-tooth) was very small but still measurable at just 0.49 watts – similar to what others have calculated on theoretical terms. Comparing the 15-tooth pulleys to the 11-tooth ones more commonly used in modern derailleurs, the difference drops to 0.25 watts. Smith contends that the larger 15-tooth pulleys require the chain links to articulate less than with smaller pulleys as they pass through the cage, thus generating less friction between the side plates.

Subbing in the standard manufacturer's bearings – but still maintaining constant lower chain tension – extends that difference further, says Smith. A standard Shimano Dura-Ace 11/11-tooth pair of pulleys takes 2.6 watts of power compared to 2 watts on Berner's ceramic-enhanced 13/15-tooth setup.

Cage tension also apparently plays a role. In general, less tension is better than more. Smith says a stock Shimano Dura-Ace pulley cage creates 14.19N (3.19lb) of lower chain tension whereas a Berner's more lightly sprung setup creates less than half at just 6.85N (1.54lb). Taking all three factors in total (pulley size, bearing performance and cage tension), Smith measured a difference of 1.76 watts.

An efficiency gain of less than two watts is hardly earth-shattering for everyday riders and hardly practical when you consider that a ceramic-equipped Berner cage assembly runs about €359 (about US$478 or £305 at straight conversion rates). Two watts is still two watts, however, and for top-end pro riders and teams that rely on race results for their livelihoods, it's relatively "free" speed.


http://www.cyclingnews.com/features/fri ... -efficient

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PostPosted: Thu Jun 20, 2013 1:03 am 
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The chain tension observation is particularly insightful. Less tension on the chain = less resistance to bend it as it travels through the pulleys and onto the rear cog.

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