Wheels upgrade

Discussion in 'Cycling Equipment' started by mrOldcyclist, Apr 20, 2017.

  1. mrOldcyclist

    mrOldcyclist New Member

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    Has anybody heard or seen, the new coo space bearing Wheels in the American Market?
     
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  2. Froze

    Froze Well-Known Member

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    It seems bearing technology is in a transformation. The one you show is actually not the now better idea, so as fast as the Coo bearing is being introduced it may be soon outclassed with a magnetic system that supposedly will have zero friction. Of course this all depends on whether or not the magnetic bearing system can be made cheap enough to make it worthwhile for bikes whereas the Coo would be. However with as much money that cyclist spend on stuff that makes very little difference I'm sure they could sell magnetic bearings for $500 a set that could actually make a difference vs ceramic bearings...but I won't be jumping on the $500 bearing wagon just as I haven't jumped on the ceramic bearing wagon.

    If this magnetic system does indeed work and goes into production I do believe it will revolutionize all things we operate that use bearings, so one of the few things of modern technology that can be put on a bike that could actually work, perhaps significantly better than the old technology it replaces, instead of a bunch of hype pushed by pro racers and marketing to get us to buy stuff that is just a very minute and non discernible difference except in our minds.
     
    #2 Froze, May 9, 2017
    Last edited: May 9, 2017
  3. mrOldcyclist

    mrOldcyclist New Member

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    hey Great, thank you for the update info..
     
  4. dabac

    dabac Well-Known Member

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    Remember that only because something is true doesn't make i important.
    Regular ball bearings are pretty darn good as they are.
    For a cyclist the part lost to bearing friction is a few percent of the total losses.
    So a huge reduction in bearing losses, well it's a huge reduction of something that's very small already.
    Don't hold your breath.
     
  5. Froze

    Froze Well-Known Member

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    well "supposedly", and do note I put that in quotes because it is very highly debated, that ceramic bearings save up to 9 watts, which I kind of doubt, but regardless, some hubs like the Chris King do not roll as well as White Industry hubs which can be seen on You Tube, but my old 1984 Suntour Superbe hubs that have over 150,000 miles on them are still by far my best spinning hubs even to the much newer 105 hubs made 3 years ago, so I doubt I would save even 4 watts going to Ceramic.

    So now the question is how many watts does a typical hub use? I couldn't find that answer believe it or not which is silly since ceramic claims they can save up to 9 watts but we don't know how many watts a typical hub uses, I would venture a guess at around 15 to 20 watts since the savings mentioned is about 9 watts, just guessing of course. However according to everything I've read the magnetic hub would have 0, that's zero friction, thus no watts being expended to keep the wheels going from a hub standpoint. Dropping 15 to 20 watts is a significant savings that can easily be felt...IF it's all true of course.
     
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  6. dhk2

    dhk2 Well-Known Member

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    The bearing drag should be almost negligible in any decent hub that not running excessive preload. The book Bicycling Science (3rd edition, 2004, MIT Press) estimates an average coefficient of friction as .001 for the steel ball bearings. The author, Prof David Wilson, cites several references to get to this figure.

    In the illustration given, a typical load of 100 lbs on the wheel hub is used. That's 450 N of force, so the bearing drag in the hub would be 0.45 newtons, or 0.1 lbs force. But the hub radius is very small compared to the tire radius. So taking that hub drag out to the tire meeting the road decreases the drag force to 0.014N.

    The book didn't talk power loss, but since a watt is defined as a newton-meter/second, all we need to do is to pick a speed and we've got the power loss. Let's take 10 m/sec (about 22 mph) . At that speed, the small drag force of 0.014 newtons would result in a wattage loss of 0.14 watts.

    The book gives a figure of 0.004 Cr for a fast road tire on smooth surface. In that case, tire rolling losses would be roughly 2 N (.004 CRR x 450 N load). Again at 10 m/sec (22 mph), you've got 20 watts lost (per tire).....vs 0.14 watts for the hub. Even if the estimates aren't perfect, the point is bearing losses barely count in total power required.
     
  7. CAMPYBOB

    CAMPYBOB Well-Known Member

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    Many years ago I went into a bike shop. The old man that owned it had set a bunch of city-to-city 'best times'...decades before STRAVA Segments. City-to-City times used to be a popular form of 'racing'. I don't know if Frank Berras' name will Google up, but back in the day he was a fast, fast guy.

    Anyway...he had a pair of demo wheels built up on the counter of the shop.

    One wheel was a sew-up rim laced to a typical Campy high flange Record hub running with oil.

    The other wheel was an identical rim laced to a Pelissier hub running with oil.

    Oil, instead of grease, was what was used for races and record attempts. Also, Google up the Pellisier brothers...interesting history there.

    Old man Berras would tell you to grab both rims and give them an equal hard tug to set them spinning.

    The Campy hub spun down and the wheel would go back and forth and finally settle to a stop in a couple minutes if memory serves me.

    The Pelissier hub would spin. And spin. And spin. And spin. Berras claimed, and I believed him, that he could set the wheel spinning, close the shop for lunch and go across the street and eat a sandwich, come back to the shop and wheel would still be spinning.

    Drag from the spokes passing through the air initially slowed the wheel when it was spinning at its fastest, but once it took an initial slow down it seemed to coast on down forever. And even when it finally started going back and forth with the heavy spot on the rim seeking bottom due to gravity...it still took forever to finally come to a stop.

    These are the best bearings I have ever seen manufactured for a bicycle.

    Modern contact seals on bearing add more drag than the bearings, themselves.

    Here's the Pelissier hubs...

    [​IMG]
     
    #7 CAMPYBOB, May 10, 2017
    Last edited: May 10, 2017
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  8. CAMPYBOB

    CAMPYBOB Well-Known Member

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  9. Froze

    Froze Well-Known Member

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    That's interesting that Bicycling Science had the watts so low, which after some search I found this site that is telling readers that ceramic bearings friction losses that manufactures are claiming are all lies! See: http://road.cc/content/feature/175644-ceramic-bearings-pros-and-cons This is isn't uncommon for huge claims in the cycling industry which is why speeds havent gone up much at all since the early 60's in the TDF with all the advancements in frame, wheels, aero science, nutrition etc really doesn't seem to do much. The speeds have pretty much plateaued since the early 60's with the average speed going from 37 km/h to 40 km/h, that's only 3 km/h gain in just over 50 years.

    When I say the average speeds haven't gone up much one must consider that while the records show that the speeds have indeed gone up however the miles covered in a race have gone down, for example in 1926, yes that's not a mistype, in 1926 the average speed was just 24 km/h while in 2010 the average speed was 40 km/h, so you scream there is a massive speed gain...except in 1926 the race covered 5,745 miles and a lot of that was on dirt and gravel roads plus you had to fix your own flats and any other repairs plus ride a heavier bike, while in 2010 the race covered just 3,642 miles of paved roads and had a support car to provide fast ready to ride wheels should a flat occur as well as no worries about repairs with spare bikes on hand and run a much lighter more aero bike. Even in the early 60's riders were still fixing their own stuff and still had some gravel roads they had to ride on, and the miles were higher back then as well as having to deal with steeper grades to climb.

    So I seriously doubt that going to magnetic hubs is going to make any noticeable change in the average speed in races, but possibly magnetic hubs will no longer wear out like bearing hubs? regardless if they wear out or not people are nuts and will pay big bucks to get magnetic hubs if the marketers and pro racers lie like they always do and claim huge watt savings.
     
  10. Froze

    Froze Well-Known Member

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    [QUOTE="CAMPYBOB, post: 3826915, member: 97464

    The Pelissier hub would spin. And spin. And spin. And spin. Berras claimed, and I believed him, that he could set the wheel spinning, close the shop for lunch and go across the street and eat a sandwich, come back to the shop and wheel would still be spinning.

    These are the best bearings I have ever seen manufactured for a bicycle.

    Modern contact seals on bearing add more drag than the bearings, themselves.

    Here's the Pelissier hubs...

    [​IMG][/QUOTE]

    And just imagine, those hubs are old! And modern hubs today with all the technology at their disposal to make better bearings and races still can't compare to the older hubs! My Suntour Superbe hubs spin much longer than any other hubs I have, and mine after 150,000 miles have never had the bearings replaced, so I don't know about who has the best bearings but Suntour made some pretty damn fine bearings.
     
  11. CAMPYBOB

    CAMPYBOB Well-Known Member

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    IMO Campy hubs were the best as far as smoothness went. I never really tested them and always used grease as the lubricant. As a guess, later versions of Dura-Ace were probably as good or better.

    The Pelissier hubs I witnessed spinning down had a gloss gray finish and were probably late 1970's production? Again, I'm guessing. I was, to put it mildly, very impressed with them when compared side-by-side with Campy hubs.

    Bearings come in several classes and are governed by the ABEC. I doubt ANY bike bearing is designed to ABEC Class 9. That would be extraordinarily expensive and frankly, unnecessary for the requirements of even the finest racing bike. ABEC Class 9 would be used in the gyro's of an ICBM, for example...not a piece of sporting equipment.

    Ceramic will save a couple of Watts, but how many?

    The only 'Watt savings' I've ever been able to feel are from aero wheels and I 'think' from larger derailleur pulleys. I guess if we add up all the Watts savings from helmet, skinsuit,shoe covers to pulleys, chain lube, frame design, etc. I might be a mile or two per hour faster and that would be a huge gain at racing speeds.
     
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