Ceramic Bearings for added speed
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2010-01-23 6:57 AM |
New user 56 | Subject: Ceramic Bearings for added speed Has anyone here ever used Ceramic/ Silicon Nitride bearings on their bikes. I know folks pay a fortune for the low aerodynamic drag wheels and I was wondering if anyone had looked at just changing their bearings. "Ceramic" bearings offer 80% lower drag than a conventional metal bearing, they are lighter and last longer as well. A reduction in drag is a reduction in drag. I know they use these type bearings in high performance applications and wondered if it was common among you folks. My brother said in some auto racing applications they are illegal and are "good" for about 15 horsepower. There is a link below...but I am sure you can get these at your local industrial bearing house for cheaper. http://www.bocabearings.com/main1.aspx?p=docs&id=7 Enjoy! |
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2010-01-23 7:03 AM in reply to: #2630170 |
Master 2621 Mechanicsburg, PA | Subject: RE: Ceramic Bearings for added speed
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2010-01-23 8:38 AM in reply to: #2630170 |
New user 56 | Subject: RE: Ceramic Bearings for added speed That I don't really know. If I had enough time I could probably caculate the gain somehow. I imagine that the gain you would get would be at least 50% or more as significant as the gain you would get from Aero wheelsets at a fraction of the price. That is just my opinion. A efficiency gain from frictional losses is still a gain in efficiency. How much gain do you get from Aero wheelsets? |
2010-01-23 9:00 AM in reply to: #2630170 |
New user 56 | Subject: RE: Ceramic Bearings for added speed After poking around on the internet it seems that ceramic bearings make you 4% more efficient. See excerpt below. |
2010-01-23 9:08 AM in reply to: #2630248 |
Master 2621 Mechanicsburg, PA | Subject: RE: Ceramic Bearings for added speed eitek1 - 2010-01-23 9:38 AM That I don't really know. If I had enough time I could probably caculate the gain somehow. I imagine that the gain you would get would be at least 50% or more as significant as the gain you would get from Aero wheelsets at a fraction of the price. That is just my opinion. A efficiency gain from frictional losses is still a gain in efficiency. How much gain do you get from Aero wheelsets? Well that really depends on which aero wheels you run. As far as aero goes Zipp info here; http://www.zipp.com/technologies/aerodynamics/aeroedge.php The other big advantages of using aero wheel sets is the stiffness and weight. A pair Zipps 404 58mm clinchers with tires and skewers are around 4.4lbs and a pair of Felt TTR3 25mm with tires and skewers 6.6lbs. This is a comparison of stock wheels verses after market aero wheels. So the big advantage is in weigh, granted a 2k investment. Not sure what the cost per gram versa aero gain or any other stuff like that. |
2010-01-23 9:15 AM in reply to: #2630261 |
Master 2621 Mechanicsburg, PA | Subject: RE: Ceramic Bearings for added speed eitek1 - 2010-01-23 10:00 AM After poking around on the internet it seems that ceramic bearings make you 4% more efficient. See excerpt below. That is a lot! The above FSA link doesn't point to the article. btw I still ride the Felt TTR3's |
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2010-01-23 9:25 AM in reply to: #2630170 |
Extreme Veteran 385 shenandoah valley | Subject: RE: Ceramic Bearings for added speed I have ceramic bearings on my road bike (used in tris) in the bottom bracket and in my FSA wheels. I also have ceramic bearings on my mtn bikes, the 26er has bottom bracket and in the Crossmax SLR wheels. The 29er has a ceramic bottom bracket and ceramic pulley bearings (XX), but I didn't upgrade the wheels to ceramic (I-9's). I may put ceramic bearings in those wheels, not sure yet. I'm a big fan of ceramic and I could tell a difference in the wheels. On downhills, as I let off the brakes the wheels accelerate noticeably. Ceramic bearing upgrades are worthwhile in my opinion. |
2010-01-23 9:41 AM in reply to: #2630261 |
Champion 9407 Montague Gold Mines, Nova Scotia | Subject: RE: Ceramic Bearings for added speed eitek1 - 2010-01-23 11:00 AM What do these numbers mean for a rider? Well, FSA did some testing and found that a bike equipped with ceramic bearings was 4% more efficient than the same bike equipped with steel bearings. So for every 100km ridden on the steel bearing equipped bike, the ceramic equipped competition rode 104km, while expending the same amount of energy. If we assume the peloton averaged 40km/hr, that's a win by.....SIX MINUTES! Pure marketing BS. Shane |
2010-01-23 9:46 AM in reply to: #2630170 |
Champion 7595 Columbia, South Carolina | Subject: RE: Ceramic Bearings for added speed I think (emphasize think -- I'm not an expert) it is widely accepted that they are more durable, and that high quality ones are rounder and more consistent in size than steel. I've seen claims of 10W gained, but I have no idea whether it's true. A few places that cater to cyclists (some already mentioned): http://www.fullspeedahead.com/ http://www.bocabearings.com/ http://www.ceramicspeed.com/ http://www.endurobearings.com/ |
2010-01-23 1:44 PM in reply to: #2630299 |
Master 1404 Saratoga Springs, Utah | Subject: RE: Ceramic Bearings for added speed gsmacleod - 2010-01-23 8:41 AM eitek1 - 2010-01-23 11:00 AM What do these numbers mean for a rider? Well, FSA did some testing and found that a bike equipped with ceramic bearings was 4% more efficient than the same bike equipped with steel bearings. So for every 100km ridden on the steel bearing equipped bike, the ceramic equipped competition rode 104km, while expending the same amount of energy. If we assume the peloton averaged 40km/hr, that's a win by.....SIX MINUTES! Pure marketing BS. Shane The test was ran against rusty steel bearings. I have a real hard time believing that ceramic bearings would save 6 minutes over 100k, but yes I have seen reports of savings of 20-40 meters per 1k which over 100k would be an additional 2k-4k. So off of a estimated guess it looks like a speed increase of ~.8 mph for a rider going 20 mph with no additional effort? Not buying it. |
2010-01-23 1:50 PM in reply to: #2630170 |
Veteran 549 | Subject: RE: Ceramic Bearings for added speed I will be blunt. It aint happenning. We have more BS in our sport than any other by far. |
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2010-01-23 2:21 PM in reply to: #2630170 |
Elite 4235 Spring, TX | Subject: RE: Ceramic Bearings for added speed I am having ceramic bearings installed on my new bike. I decided to go all out and get all of the top of the line components, so the bike will never be my excuse for going slow.
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2010-01-23 2:54 PM in reply to: #2630170 |
over a barrier | Subject: RE: Ceramic Bearings for added speed I can't find the source anymore, but the ceramic BB saves less than two watts. It was 1.XX savings...up to you if that is "worth it" |
2010-01-23 3:02 PM in reply to: #2630638 |
Champion 8540 the colony texas | Subject: RE: Ceramic Bearings for added speed what about ceramic bearing with dimples?? |
2010-01-23 6:40 PM in reply to: #2630654 |
Master 2372 | Subject: RE: Ceramic Bearings for added speed Gaarryy - 2010-01-23 3:02 PM what about ceramic bearing with dimples?? Those came off the spaceship from Roswell and are still classified by the government. Sadly we can't get any this time. |
2010-01-23 8:10 PM in reply to: #2630170 |
Regular 84 California | Subject: RE: Ceramic Bearings for added speed The benefit from ceramic bearings is absolutely minimal. They are originally designed for high speed applications where heat management was very important to reduce thermal expansion - applications where the rpm's may be in the thousands per minute. At 40km/h your wheels will be spinning at slightly over 300rpm - significantly below the speeds where ceramic bearings may provide heat management benefit. As far as speed benefits go, there is hardly any benefit because there is hardly any thermal expansion and additional friction. There is no data that shows that if I get a wheel with standard bearings and spin it at a certain speed, and compare the same wheel with the ceramic bearings, the latter will take longer to get to a stop. |
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2010-01-23 10:21 PM in reply to: #2630170 |
New user 56 | Subject: RE: Ceramic Bearings for added speed I agree that ceramic bearings excel in high speed/ High temp applications and a bike isn't one of them. That doesn't mean that the other benefits that come along with ceramic bearings won't be realized. Think of it like this. Ceramic bearings are "rounder" than conventional steel bearings and have a harder more uniform surface area. Due to this they have a tendancy to deform less under load. I agree that the deformation will be absolutely minimal but it will be there. For hypothetical reasons lets say you are riding in a vacuum. You suddenly stop pedaling and start coasting. Will you go farther on a bike that has steel wheel bearings or one that has ceramic wheel bearings? My guess is that you will go farther on the one that has ceramic wheel bearings. I would guess you would actually go a lot farther. If that is the case and I am right then there is some gain to be had with ceramic bearings. Is it in line with how much they cost, I dont' really know. Here is a link from a website where they tested various bearings to measure losses. They brought the flywheels up to speed using a motor. On the ceramic bearings at speed the motor used 10% less energy to keep it moving. That is huge. http://machinedesign.com/article/ceramic-bearings-save-energy-extend-life-1005 "At 3,000 rpm on the bench-top flywheel setup, the all-ceramic bearing used 1.25 W less power than the all-metal and metal-ceramic hybrid bearings. The flywheel drive motor drew 10 to 12% less current when running ceramic bearings than when metal-containing bearings were used." I found where they actually did the test in a vacuum on a rotating disc to see how much drag a bearing seal made. What they found was the one with the best seal rolled 400+ feet farther than the "standard". Keep in mind this is just the difference in seal types. I found a great write up on the actual reasons for drag on a bicycle. It's a great article. http://www.slowtwitch.com/Tech/The_Physics_of_Moving_a_Bike_163.html I don't really actually care either way. I am not fast enough or do I have enough money to justify Aero Wheels or Ceramic bearings. I just thought this would be an interesting discussion which it is. Heck, I just got clipless pedals and was kind of proud of that |
2010-01-23 10:31 PM in reply to: #2631179 |
Champion 7233 | Subject: RE: Ceramic Bearings for added speed FWIW i had a set zipp 808 front, and a blackwell 100. zipp had ceramic bearings. both were spun at the same speed with the bike upside down both ended up stopping at the same place (within according to the SRM 2 feet of each other. now, i am pretty sure there is more computer error in there than that. i could 100% not tell a single diff spinning them, or riding them, |
2010-01-24 4:30 AM in reply to: #2630170 |
Pro 5892 , New Hampshire | Subject: RE: Ceramic Bearings for added speed High quality steel bearings can be better than the average ceramic bearings... just because you utilize a material doesn't necessarily mean that you will gain anything from it if not properly implemented. That being said, high quality ceramic bearings are noticeable smoother, but I really don't think they are that much faster... over a 40k TT, I would guess it wouldn't be more than a handful seconds at most. We're getting very thin on the return on investment... but if you like the feeling and have the money, why not... they will last a very long time if maintained (cleaned and greased). Full disclosure- I do have bikes both with steel bearings and other bikes with ceramic bearings. |
2010-01-24 9:52 AM in reply to: #2631179 |
Regular 84 California | Subject: RE: Ceramic Bearings for added speed eitek1 - 2010-01-23 8:21 PM I agree that ceramic bearings excel in high speed/ High temp applications and a bike isn't one of them. That doesn't mean that the other benefits that come along with ceramic bearings won't be realized. The original question though was if ceramic bearings will make a bike ride faster, where the bike wheels have lower RPM's and certainly do not operate in a vacuum. The test setup you described is good for evaluating the properties of a bearing under certain conditions, but they are by no means relevant to a bike which operates under very different conditions. Nor does it tell you anything at all about the gain in speed / time / power versus traditional bearings. Think of it like this. Ceramic bearings are "rounder" than conventional steel bearings and have a harder more uniform surface area. Due to this they have a tendancy to deform less under load. I agree that the deformation will be absolutely minimal but it will be there. For hypothetical reasons lets say you are riding in a vacuum. You suddenly stop pedaling and start coasting. Will you go farther on a bike that has steel wheel bearings or one that has ceramic wheel bearings? My guess is that you will go farther on the one that has ceramic wheel bearings. I would guess you would actually go a lot farther. If that is the case and I am right then there is some gain to be had with ceramic bearings. Is it in line with how much they cost, I dont' really know. Here is a link from a website where they tested various bearings to measure losses. They brought the flywheels up to speed using a motor. On the ceramic bearings at speed the motor used 10% less energy to keep it moving. That is huge. http://machinedesign.com/article/ceramic-bearings-save-energy-extend-life-1005 "At 3,000 rpm on the bench-top flywheel setup, the all-ceramic bearing used 1.25 W less power than the all-metal and metal-ceramic hybrid bearings. The flywheel drive motor drew 10 to 12% less current when running ceramic bearings than when metal-containing bearings were used." I found where they actually did the test in a vacuum on a rotating disc to see how much drag a bearing seal made. What they found was the one with the best seal rolled 400+ feet farther than the "standard". Keep in mind this is just the difference in seal types. I found a great write up on the actual reasons for drag on a bicycle. It's a great article. http://www.slowtwitch.com/Tech/The_Physics_of_Moving_a_Bike_163.html I don't really actually care either way. I am not fast enough or do I have enough money to justify Aero Wheels or Ceramic bearings. I just thought this would be an interesting discussion which it is. Heck, I just got clipless pedals and was kind of proud of that |
2010-01-24 10:42 AM in reply to: #2630170 |
Elite 3658 Roswell, GA | Subject: RE: Ceramic Bearings for added speed Ceramic bearings would be one of the last upgrades I would make. The science behind the claims is shaky and the gains are most likely very small.
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2010-01-24 12:54 PM in reply to: #2631521 |
Champion 7233 | Subject: RE: Ceramic Bearings for added speed brown_dog_us - 2010-01-24 9:42 AM Ceramic bearings would be one of the last upgrades I would make. The science behind the claims is shaky and the gains are most likely very small.
this is why my money is going to race entries, food so i can recover from them, and high quality tri suits so they are not acting likea sail in the wind and water;-) |
2010-01-24 4:34 PM in reply to: #2630303 |
Champion 6503 NOVA - Ironic for an Endurance Athlete | Subject: RE: Ceramic Bearings for added speed Experior - 2010-01-23 9:46 AM I think (emphasize think -- I'm not an expert) it is widely accepted that they are more durable, and that high quality ones are rounder and more consistent in size than steel. I've seen claims of 10W gained, but I have no idea whether it's true. A few places that cater to cyclists (some already mentioned): http://www.fullspeedahead.com/ http://www.bocabearings.com/ http://www.ceramicspeed.com/ http://www.endurobearings.com/ 10 Watts??? I'd give you the tip of my right pinky for 10 watts! |
2010-01-24 4:38 PM in reply to: #2630558 |
Champion 6503 NOVA - Ironic for an Endurance Athlete | Subject: RE: Ceramic Bearings for added speed kdlsch111 - 2010-01-23 1:50 PM I will be blunt. It aint happenning. We have more BS in our sport than any other by far. I beg to differ. You need to look a little closer at golf. There was a golf shoe that guaranteed (thats right, guaranteed) another 10% on your drives. And they had a tour player who backed it up. n=1 |
2010-01-24 6:20 PM in reply to: #2631981 |
Champion 7595 Columbia, South Carolina | Subject: RE: Ceramic Bearings for added speed pga_mike - 2010-01-24 5:34 PM Experior - 2010-01-23 9:46 AM I think (emphasize think -- I'm not an expert) it is widely accepted that they are more durable, and that high quality ones are rounder and more consistent in size than steel. I've seen claims of 10W gained, but I have no idea whether it's true. A few places that cater to cyclists (some already mentioned): http://www.fullspeedahead.com/ http://www.bocabearings.com/ http://www.ceramicspeed.com/ http://www.endurobearings.com/ 10 Watts??? I'd give you the tip of my right pinky for 10 watts! Maybe we should start a new government plan: "Watts for Body Parts". Or maybe a new online auction concept? Obviously, as I said, I have no idea whether the claim is true. One example of it (it shows up other places) is here. |
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