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So, new pedals are slower right?
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When I spin my regular pedals they whir and spin into a blur and at least 20 times before slowing down - eventually slowling down due to the unbalanced weight distribution due to the shape. When I spin my new ultegra pedals I am lucky to get one turn, its almost like they have a handbrake on

Bascially you could say my old axel turns like a spoon stirring tea, and the new axel is more like a big wooden spoon in pancake batter. This extra resistance has to add up to overcome constantly across a few hours right?

So the question is are new pedals with thick grease sucking huge watts through excessive viscosity?

- has anyone looked at this?
- is there any bearing between the finger spin test and actual biking resistance?
- does grease turn molten under the pressure of a pedal stroke? and if so is the grease molten under load but the other 80% of the bearing still viscous at any one time?
- does grease turn more liquid as it heats up from friction of biking? or is this pretty stable? I havent stopped to check if the finger spin is better after riding for some minutes
- or do new pedals need to be broken in to get that friction down initially?
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Re: So, new pedals are slower right? [lacticturkey] [ In reply to ]
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Doubt it makes any real world difference.
Kind of like how ceramic bottom brackets spin faster in the work stand...
And, they will probably work in a bit over a few hundred kms
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Re: So, new pedals are slower right? [lacticturkey] [ In reply to ]
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lacticturkey wrote:
When I spin my regular pedals they whir and spin into a blur and at least 20 times before slowing down - eventually slowling down due to the unbalanced weight distribution due to the shape. When I spin my new ultegra pedals I am lucky to get one turn, its almost like they have a handbrake on

Bascially you could say my old axel turns like a spoon stirring tea, and the new axel is more like a big wooden spoon in pancake batter. This extra resistance has to add up to overcome constantly across a few hours right?

So the question is are new pedals with thick grease sucking huge watts through excessive viscosity?

- has anyone looked at this?
- is there any bearing between the finger spin test and actual biking resistance?
- does grease turn molten under the pressure of a pedal stroke? and if so is the grease molten under load but the other 80% of the bearing still viscous at any one time?
- does grease turn more liquid as it heats up from friction of biking? or is this pretty stable? I havent stopped to check if the finger spin is better after riding for some minutes
- or do new pedals need to be broken in to get that friction down initially?

Did you spin the axles before fitting?
If they feel a little rough they needed adjustment, it's a 5 min job, just like adjusting preload on any other bearing.
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Re: So, new pedals are slower right? [SBRcanuck] [ In reply to ]
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Also remember they’re only rotating about 1.5 times a second...

OTOH I sense a new market for ceramic pedal bearings :D
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Re: So, new pedals are slower right? [MattyK] [ In reply to ]
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MattyK wrote:
Also remember they’re only rotating about 1.5 times a second...

OTOH I sense a new market for ceramic pedal bearings :D

Time has used Ceramicspeed bearings in their highest end pedal for a number of years now!
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Re: So, new pedals are slower right? [MattyK] [ In reply to ]
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They turn at the same speed as the crankset and marketing moguls have persuaded those with disposable income that ceramic crank bearings are something you must have, so yes there would be a market if changing them was as easy as changing other bearings.
All of the bike ceramic bearings on offer are simply standard size bearings relabeled with some marketing bullshite and sold for stupid money, pedal bearings on the other hand are mostly very specific to that pedal so you cannot just smack on your own rebadge and make money.
Even though there is more power loss in a pedal bearing than a crankset, it is not an easy target for the money grabbers.
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Re: So, new pedals are slower right? [lacticturkey] [ In reply to ]
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How do the spin fully weighted and with 2-300 watts being applied to them? My guess is that the added weight will displace a lot of the grease/lubricant and make the new pedals more efficient.

There are definitely some watts to be saved here, just like there is in jockey wheels, bottom brackets and chains, but pedals are a bit more complicated because of the direct contact with the rider which makes it more difficult to test
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Re: So, new pedals are slower right? [SBRcanuck] [ In reply to ]
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SBRcanuck wrote:
Doubt it makes any real world difference.
Kind of like how ceramic bottom brackets spin faster in the work stand...
And, they will probably work in a bit over a few hundred kms

Agreed. And most of what is slowing the rotation down is probably seal drag, not bearings. That should improve over time.
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Re: So, new pedals are slower right? [lacticturkey] [ In reply to ]
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Hello lacticturkey and All,

I did a test some time back wrapping a string around the spindle of a SpeedPlay pedal with a weight attached to it and measured the time for the weight to unwind a measured amount of string while spinning the pedal.

I did the test after lubing the pedal with the approved SpeedPlay grease gun and grease.

Then repeated the test after flushing the grease and using a very low viscosity synthetic automotive engine oil.

The results led me to believe that the fractional Watt saved with superior lube was not 'worth the candle'.



Also notice that the friction values for various bottom bracket bearings are small and subject to the same magnitude of force as a pedal spindle.

https://www.bikeradar.com/...-bracket-drag-39233/

Excerpts:

"Ceramic bearing-equipped bottom brackets – or hybrid ceramics, to be more precise – are generally much more expensive than their stainless steel cartridge-equipped brethren. Manufacturers claim that they're not only faster by virtue of generating less friction, but in some cases, also more durable.

Friction Facts' new jig isn't equipped to test durability but in terms of drag, the ceramic myth has been thoroughly debunked.

"Bottom Bracket efficiency is predominantly based on the design and the quality of materials used, not the material itself," Friction Facts principal Jason Smith wrote in his latest report.

According to Smith's data, the difference in drag between the top steel model (0.32W) and the best ceramic model (0.29W) was just 0.03W – virtually nothing. Moreover, out of five manufacturers with comparable steel and hybrid ceramic models, three actually posted lower friction values for the steel models than for the otherwise identical ceramic ones." [emphasis added]



Cheers, Neal

+1 mph Faster
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Re: So, new pedals are slower right? [nealhe] [ In reply to ]
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in the old days, of course, with unsealed caged ball bearings, we were free to adjust the pressure of the races on the bearings and to grease or oil them as we so chose. were that to come back, with some liptstick, it would be the tech innovation of the year.


Dan Empfield
aka Slowman
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Re: So, new pedals are slower right? [nealhe] [ In reply to ]
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Thanks nealhe! That's very interesting, I wouldn't have expected the difference to be next to unmeasurable😊

0.03w of 0.27 is 10 percent more friction per side? If this is similar to the difference for pedal friction, would I be able to feel the difference just turning the pedal back and forth unloaded? Because for me I can easily tell with eyes closed which is the new pedal. If there's 10 percent less friction then if you finger spin the pedal you might expect 4 turns instead of 5 instead of the 0.5:5 ratio roughly (the 20 before was hyperbole). And even then I think odd pedal weight distribution is the limiter not even friction so the friction difference could be greater?

If power = force per time.... What is time?
o. 3= force per any given second or per revolution or per minute or per hour?

I guess if its deemed insignificant then it must be per hour?
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Re: So, new pedals are slower right? [lacticturkey] [ In reply to ]
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Hello lacticturkey and All,

I think it is important to consider that spinning an unloaded pedal does not imitate the actual pedal function when loaded in use .... when you are standing to go up a hill .... and my experiment did not mimic the loaded condition .... so take it with a grain of salt.

It is under loaded conditions that you want the best pedal performance.

It appears that the total loaded pedal friction is likely on the order of 1 Watt ... doing a WAG from the published tests of bottom brackets.

And different lube from my tests showed little effect overall ... unloaded.

The upshot is that I keep my pedals lubed with grease (infrequently) or oil (frequently) and do not think about that aspect any more .... and I probably wasted my money getting the ceramic bearing version of the Speedplay pedal.

Cheers, Neal

+1 mph Faster
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Re: So, new pedals are slower right? [lacticturkey] [ In reply to ]
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Friction Facts have a report on pedals that included the last generation (6800) Ultegra pedals; I won't divulge the full results, but the Ultegras scored well compared to the competition. Not sure if it they used a run-in period and obviously their results are only applicable to them as they are supplied (e.g. with stock bearings & lube).

The Ultegras are a standard ball-and-cone assembly so you wouldn't expect them to improve much with running in (and this correlates with my experience) but on the positive side, this means I reckon there's a fair bit of room for improvement if you're into stripping and regreasing everything.

I've always been keen to strip mine down, but they're currently my only set of pedals and I've heard they can be a bit finicky in terms of getting them running smoothly and quietly again.
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