Will A Ceramic Bottom Bracket Make You Faster? | Marginal Gains
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- Опубліковано 9 лют 2025
- I got a chance to run a BB Infinite ceramic bottom bracket on my diamondback. I went out and tested it with a stock bottom bracket, then tested it with the ceramic bottom bracket from BB Infinite.
Results were pretty cool, and its hard to dispute the data, no matter how small they are. I saw an increase in speed with the same power output over 4 tests each.
It would be super cool if you gave BB infinite a look, no promo code or anything as I am not getting paid for any of this, but I like them and think they make a difference.
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Ceramic bbs always look good with no load. but under load they may act very different as anyone can pack light grease into some bearings and have them spin easy in a stand
Hey VG, nice vid. I've installed the one piece BBInfinate BB. I did this more because I own a Cannondale and the machining tolerances are garbage so my BB is prone to creak. So really the one piece design is what I wanted primarily. Now I could have gone with steel bearings, but I chose ceramic. After doing more research (see the Hambini channel) I've discovered ceramic is marketing spin. The bearings that are the best bang for buck, last longer and have equal performance to ceramic are steel bearings with non-contact seals and steel stamped cage like the NTN bearings. Research has shown that the little rubber seals on the bearing create resistance as does the lesser quality plastic cage. Now if you want out-in-out performance and don't mind pulling out your BB every few months to service / replace, then simply buy steel bearings with a steel cage and throw away the seals. I've seen this as a strategy with other cyclists who simply buy cheap bearings, spray liberally with a very low friction oil and throw away the seals. Yes the bearings get full of crud and get destroyed but the cost of the cheap bearings means they can afford three sets of cheap throw aways, for the price of one set of ceramic with the same performance.
How is that bottom bracket and ceramic bearings holding up 3 years later?
@@Jolinator The one piece BB is a winner, bearing life is excellent and spins great with ZERO creak EVER. I've since gone with Hambini BB's on my new Cannondale frame and it is impressive machine quality. A one-piece is an excellent solution for 30mm pressfit BB's.
@@PeterPutz82 Im looking to get a pf92/bb30 setup so was curious how those ceramics held up or if i should just get the abec 7s, seen hambinis videos on ceramics and agree its not really worth it but they offer a lifetime replacement warranty which seems decent given its only 55$ more. BBinfinite use a 4030 bearing on their pf92 bb30/dub bb which seems exclusive to them, hambini doesnt offer anything for pf92/dub which is what my scott spark rc runs. Cheers
@@Jolinator Hmm, not sure, I buy my NTN bearings direct from Hambini as finding the non-contact seal bearings is difficult. Honestly, you're talking 1 or 2 watts in friction loss. Ceramic is marketing spin, a good qaulity steel bearing is comparable in performance with a longer bearing life. You'll get far larger gains and bang for buck looking at wheels or your own riding position to maximise watts / lower drag. Really ceramic bearings and OSPW systems are for the pro's where every watt counts, for the rest of us, spend your money elsewhere.
@@PeterPutz82 Yeh got it was more thinking if the bearings go bad in a couple years at least i will get a replacement set free which works out the same cost as buying their regular bb. Most likely will just go for regular abec-7s. how many miles did you put on that bottom bracket? Hopefully the 4030 is available to everyone else soon as i hate bispoke bearings but not many good options for pf92/dub/bb30 setups
Do a test on beard aero vs no beard
My understanding is that ceramic bearings, being harder than steel, allow you to use lighter grease which reduces friction. This is at the coat of wearing out the bearing race faster since it is still made of steel and again steel is softer than ceramic.
However, the main cause of friction in bearings you'll find on bikes is not the grease... It's the bearing retainer and dust seal. So I don't see how ceramic would be measurably faster (if faster at all).
As others have mentioned this experiment would be much better done on zwift. Also the margin of error in your powermeter is an order of magnitude greater than the variance in the results.
Exactly my thoughts
Yes
I've been riding Campy for more than 30 years. I can tell a difference between the old school BB and the new BB. But when it comes to the marginal difference between steel and ceramic, is that, your body will adjust to the load you add or reduce on any effort. Meaning that, at the beginning, you'll feel the difference. But, over time you go back to the same rhythm you have become use too
Great stuff man. I only have two little suggestions going forward.
First is try to avoid confirmation bias in the future as in don't repeat test again because you think the initial result isn't right because it didn't meet expectations like at 5:45 - 6:20 . A difference of +/- 2-5 seconds over 3 or even 13 minutes could be down to wind, temperature, tire pressure and even line choice variances.
Second, if you did longer tests (30 min - 1 hour) at a slightly lower power in the early morning / late evening, you will probably get more consistent results where time differences didn't fall within the standard of deviation.
Other than that looking forward to all the other stuff you're testing.
+Seags great suggestions, I chose that section though because there really is not any wind. But I just got so confused when I saw a 2 sec difference.
I also need to control my speed going into the start of the segment. So like on the 2nd ceramic run, I was going really slow into the start. So my start speed was much lower resulting in the same time as the stock.
It's my first attempt and I have a lot to improve on but I think it will be a series. Thanks for the suggestions
I have BBinifinite bearings and I’m happy. I can tell you their customer service is off the charts good. Amazing, actually.
Would have been interesting to see what the difference was without the sand lol. Great video, thanks for your data and work!
Yo Tyler, don’t know if you’re still getting feedback on an old vid but next time you do a test like this you have to EITHER hold the same power or hold the same cadence but not both. If CADENCE (same distance will be covered), time should be the same but you’d hope see the difference in power necessary to cover the same distance (easier to keep the same speed if less friction). If POWER then hope to see a difference in time for the same output (get more speed out of same power output due bracket efficiency). Make sense? By looking to control both you mix up the variables and scramble the data. Pleas don’t listen to the engineer haters. I think these real world somewhat subjective tests have great value for us. Keep it up!!
I'm really excited to follow this series on Marginal Gains. This is going to be super dope, thanks for doing this!
Excited for this series!
Isn't the only fair way to do this is by using a motor on a stationary trainer? This way you can control the exact power and remove all other variables and then test to see what difference various components make over the course of 1 minute... 5 minutes.... 60 minutes.... 6 hours at power X? Even if the advantage is 0.5% this seems like the only way to realistically get that
For the BB it makes sense but not for any of the other stuff he's planning on testing.
That's probably what they do in lab. But at some point you have to put it to the test in real environment.
+GoustiFruit φ Well... not really for performance improvement testing... what you have to test is that it holds up. Such as do a lab test, ride it for 1000 miles, then repeat the lab test to see how well it holds up. But a lab test makes way more sense for determining the effectiveness of this sort of upgrade.
Yeah I more meant to see if mathematically you can show a benefit from the components than test outside to see how well those transfer in a real world setting
Maybe not the aero stuff, but testing drivetrain (BBs, pulleys, chain lube) and rear hub upgrades the trainer seems to make a great deal of sense...assuming one clamps with the same force and uses the same air pressure in the rear tire. Actually, the trainer is often how I learn my rear wheel's bearings are shot--the speed usually goes down by at least 1mph versus comparable efforts. Looking at Vegan's BB, I'm wondering if the time savings comes from a shot BB?
I appreciate the time and effort necessary to present this data. 😊
I'm fairly confident that experienced cyclists who race in Time Trials know the significance of "5 seconds" in the race outcome...1st place and 2nd place can be as little as 5 seconds or less. I'm a taller cyclist at 6'6" tall. 5 seconds is a big deal to me...if I can gain that much or even more by a variety of permissible advantages...you bet I'm gonna go for it.
With Same power and cadence of course it takes the same time! The thing is that keeping 300w with the ceramic should be easier
Exactly lol, he didnt even understand what the improvement would be xD omg..... Instead of doing 300 watts pure power he might have felt 299.6 Watts output xD
If you do changes on the drive train (long crank can short, ceramic bottom bracket vs steel, oiled chain vs waxed chain etc.), you could test on a smart trainer. Set the smart Trainer to erg mode at a certain wattage (300w for example for 10 minutes). The Software (Zwift, Trainer road etc.) that controls Erg mode need to be connected only to the direct drive smart trainer as power readout. Now you need a second power meter (crank or pedal based) that is connected to a head unit that also stores the data of the same ride. Now after several runs with each set up, you can compare. Obviously, you should have averaged a very steady 300w at your rear wheel. The interesting but should now be the readout of your head unit. This will tell you, how many watts you need to put into you pedals, in order to get 300w to your rear wheel. This is about as accurate as a normal person can test drive train losses and gains. I did this for several systems. Since you have -/+1% in accuracy of each, the power meter and the smart trainer, you need to do several runs, and at best do runs with only one variable changes (only testing oiled vs waxed chain) and then compare all the things combined (so a bike with oiled chain, steel BB, longer crank, and a smaller gear ratio VS a bike with waxed chain, ceramic BB, shorter crank and a bigger gear ratio). The final result for me was 10-12 watts in total, with the chain being the biggest single factor (at 300w and a 95 cadence).
Gee..there is so much wrong here. Where do you start? FIrstly, in a valid test the rider does not know which wheelset he is using; this eliminates rider bias and pigmelian. Secondly, in a valid test all the variables except the test item, are kept the same, that way you actually know what your measuring. Your anecdotal tests mean nothing because all your measurements are invalid. It seems dangerously close to an endorsement because you felt obligated to the supplier.
I put a BBInfinite bottom bracket on my Cervelo S3. I wasn't after marginal gains so much as a quiet bottom bracket (it's silent, no creak) and due to the solid shell, it is stiffer than the stock two press-fit cups. The benefits of the BBInfinite are having the bearings perfectly aligned so it spins beautifully compared to the misaligned two-cups of typical press-fit bottom brackets.
Take the old bottom bracket and remove all the grease. Use some very light ceramicspeed grease and only repack them with 50-60% grease for less drag in the bearings. I believe this is the secret behind ceramic ball bearings. Less grease og lighter grease = less resistance. Of course dirt will enter much faster.
It's easy to get caught up in claimed marginal gains. It seems like if you get all of the aero gear you'll finish before you even start
Marginal gains is bunk. Spend ever more cash to get less benefit. Only a few can afford it. Cycling (pro cycling and mainstream cycling) are averse to ground breaking gains by design change (rather than tech change), because they accept a df as what to base gains on. Go different! Go monocoque fully enclosed streamline recumbent. For less than $2000 homebuilt or 4000 secondhand, you could have a 30-50% speed gain, carry all your shopping, be fully weatherproof (cold, rain, wind) and ride in comfort. Just a taster.
Just fitted a Hambini Racing BB with top quality ultra low friction steel bearings and increased by FTP by 12% instantly. Ultra stiff and smooth. Much cheaper than Ceramic speed equivalents.
If you could do a test with a big gear and as a dancer, I think the difference would be greater. Because there is more torsion on the bearings and that was the advantage of the full ceramic bearings, but it stopped them from breaking too much because of the torsion now only the ceramic balls on the bottom bracket.
Never explained why a bottom bracket WOULD make you faster. I have no idea.
I'm not sure if I'm getting this right but you tested a dirty, uncleaned BB vs a brand new/virgin ceramic BB. I'll bet you the dirt and grime in the original BB may have sapped a lot of watts so this comparison might not be apples to apples. Regardless, really appreciate the comparison as it's very fascinating!
This kind of things only works when matched with other high end stuff and only makes sense under competition events
so you compared your dirty old stock bb against a new ceramic one in a non-controlled environment to get less than a statistically significant 5% difference? must be broscience...
got here prying around for information on ceramic bearings. nice take on it. oh and you don't know how sand got in there when at 4:00 there is literally a gaping hole at the seattube.
This is quality content. Best vegan cycling channel
The benefit of ceramic bearings is biggest by putting them in your wheels. Very little in the bottom bracket bearings, a little in the slightly larger (12) jockey wheels. It’s the wheels for that gain. Also, need to ride at 20 mph plus to get biggest benefit. They won’t help you climb.
did they clean the drivetrain for you at the same time?
that was a marginal gain too
probably more than marginal. That can easily save you 2-7 Watts.
Great video! I went with the BBinfinite standard BB and love it! It got rid of my BB30 creak! I wonder what the comparison would be between the standard BBinfinte and the ceramic BBinfinite. This would remove the engineering advantages of the aftermarket design.
Also... Do you have plans to do a marginal gains video on the Oval chainrings vs. the round? A friend of mine recently switched to the ovals and i would say, viewing first hand, that the gains are much more than marginal. Not to mention is it a coincidence that Chris Froome switched to these, I think when he won his first TDF and has pretty much won each time he's made it to Paris since making the switch. I even saw a picture from this years TDF TT stage where he has the oval on his TT bike. I don't have them and initially told my friend he is using "cheater" rings vs becoming a better rider but since watching him make huge gains and pretty much lighting up the PR tree on Strava and making it onto several top 10 all time list, has caused me to do the research and it is impressive. With all that said I hope you do plan on doing a Marginal Gains segment with them. Love the videos and thanks for doing what you do!
Position is king. That's what there is to show.
That being said, keep making the videos because.... videos :D
I'm also curious about the larger size rear jockey wheels, and if they offer some real world gains
I like your idea, but the problem is that your power meter most likely is only accurate to itself by plus or minus a 1 percent. You won't be able to accurately measure the marginal gains, IMHO.
It can be done, but you need lots of replication to randomize and average over confounding factors (e.g., environmental differences). You will then need to use statistics to see if the distinguish between the random noise versus the actual effect (i.e., the difference is not explainable by random noise). You will probably need 10-20 replicates of each treatment (i.e., a specific segment and a particular BB).
also a strong gust of wind or a slightly different aero position could completely skew the results
IT's actually more like 5% according to www.ncbi.nlm.nih.gov/pmc/articles/PMC5950748/
I’ve just ordered one man. Can’t wait. I’m going to spin to win like Chris Froome before his silly accident.
Great videos. You have the best content on cycling in UA-cam. I like how you explore other realms of cycling. Keep the videos coming.
My B.B. Infinite bottom bracket sons so freely compared to my dura ace B.B. I guess I’ll be saving my money now.
you should do a wheel test similar to what GCN did at one point! Get your 20 minute power, and ride in a fixed position on a flat road with BOX rims (not aero), and find your speed, and then put your aero wheels on (hie I think) and try to hold the same speed, and see how much farther you can go! (keep in mind you're going to need a pretty long stretch of flat road so I don't know how easy that is to find where you are)
you should do an oval chainring test
Lol!!!!!hqhahahhahaha
great video 👍 , 2 seconds make a very alot huge difference if a serious cyclists
they cleaned your chain during new bb installation. needs a re-test when chain gets as dirty as before
Kaliburation
Exactly what I was thinking, that can save 11 watts.
Having not read through all of the comments - apologies if I overlooked this. The savings that you have no variable for is FORCE. Fully explained - The difference between the two BBs could be that it takes less overall energy to reach your planned RPM and POWER. The only way to test for this would be in a lab setting.
Actually input force is fully covered. The power meter itself does not measure power, it measures force and it measures rpm and it does the calculation to derive a power figure. More friction in the BB requires more force to maintain the same speed.
I know all the scientist and engineers are freaking out right now. Calm down peeps... it will still be fun to watch this series.
Agree with Jake R below, your results likely not statistically significant. Could negate the effect of wind and control power more precisely testing on a dynamometer (indoor smart trainer). To me main appeal of that product would be increased durability because the one piece shell is a great way to align and support the bearings.
Not ceramic, but I put an ABEC 5 steel bottom bracket in my time trial bike, the theory being that the balls being ground to a "closer to perfect" sphere also presents some gains, whether ceramic or steel. Seems to be very smooth, and no noise.
yeah taylor indeed, if you put in the same but new bottom bracket the first few rides you can really feel the difference, same with a brand new chain. but as soon as it gets used its back to baseline :)
I was hoping you do a sprint test of some sort or dancing up the hill, just beating the bottom bracket. One big characteristics of BBinfinite is the rigid single module that prevents the bottom brackets from twisting the bearings out of alignment - which is supposedly to eliminate creaking sound. However, I'd be curious to see if holding that left, right bearings in a fixed position will benefit in anyway for power transfer when you really put down the effort, shaking the bike left and right. :D
Easy the best cycling channel out there.
3 seconds on a 13minute segment isn't huge, it's 3 over 800-sum seconds = 0.4% improvement (I rounded up in the favor of the bottom bracket). If you can keep your weight that consistent over multiple days I'd be impressed. Seemed pretty legit on the short climb, would have been nice had you done 3 max sprint and see if the ceramic "unleashed" a couple friction watts.
Ideas for other videos: add a kilo of water (1liter) and see how much it cost you in seconds, latex tubes would be interesting over longer distances, dirty chain vs clean chain (same day)... Cheers Tyler, aren't you busy being a double dad now?
+Emile Goguely not a double dad yet... and I was so confused about the long climb. Short climb seemed really impressive but then those same results were not repeated.
And I did some max efforts but they were pretty all over the place.
Nice video ! Because you speak of marginal gain, it is likely that you will not even notice this gain since it is marginal. So many parameters enter into play such as the wind but also your weight was have changed between the 2 tests. the more cars overtake you the fastest you will climb. Good luck for the next tests :)
Thanks mate. I like your ideas. Have you considered using the Chung method? And buying a portable weather station to help factor weather changes into the calculations?
Different days. Air pressure and humidity alone could make that difference.
Great video, looking forward to the rest of the series
I think there's a difference between a laboratory test that can validate X% improvement and real world conditions where all of the uncontrollable variables invalidate X% laboratory verified improvement. So I respect what he set out to do here; which was determine actual perceived improvements in a world environment. If you're deciding whether to upgrade your bearings, you might see the totally negligible gains here and decide to buy another jersey instead.
I’m getting a new bracket as my old one needs replacing. But I think the price of the ceramic stuff is a little steep for me after watching this video. Especially when the gain may have been similar with your stock BB being super clean? Great video though, and very helpful 😃
I like Bbi parts. I have their jockey wheels in 2 of my bikes and I've been eyeing up their bb30 set up.
Great video.
Made in the USA is my marginal gain. If I feel good about what I'm riding I feel good riding.
I did a recent test of similar idea. I have 2 frames, a REAL Pinarello F8 (F8) and a chinese knockoff F8 (**CF8). Both built up with SRAM Red 10sp (cause I dont need 11 gears).
(F8) has old Zipp 303 10sp (circa 2009) fitted with Corsa Speed 23C tyres at 110psi and weighs in at 7.2kg with pedals and cages
(**CF8) has Vision 30 11sp with Specialized Turbo 25C tyres at 110psi and weighs 7.9kg with pedals and cages
Circuit: I have a hotmix hills circuit of 8kms and I do 4 laps in about 1 hr and a bit
Test: Ride both bikes as fast as I can for 4 laps and check the strava times. (separate days after suitable rest and food)
Results: The real F8 with Zipps and Corsa Speeds was faster BUT by how much was a real shock
My 1st lap time was bettered by 47secs over the (**F8) with low end wheels and tyres. That's 47secs quicker in 8kms
My 4 laps time was bettered by over 6 minutes. That's 6mins in 24kms
Next is to swap the wheels and do it again to find the frame influence.
Cheers
You should try ceramic BB with ceramic jockey wheels and ceramic wheel bearings and see if the combo of all that makes for a more noticeable difference.
It feels like it's been a month since this video, I love your videos sooooo much, they are my favorite.
Do it in the track, the wind will not be a big disturbance.
I might be very wrong, but I'd only expect to see an increase in speed by being able to get onto a harder cog (BUT, if the ease provided by the ceramic BB wasn't enough for getting onto another cog at all, then speed variations would be barely perceptible). Then, where did the ease provided go? I think it would go to YOU, VC. And the only way for you to show us that gain on ease with stats, would be with Heart-Rate. I'd believe you if you said "producing the 300W on the ceramic BB was easier". I trust feeling. But the stat "required" to show fatigue probably is HR, and I didn't see it.
Isn't applying 300 watt always going to give you the same time? Shouldn't you go for a set time and see what watts you are saving between the 2 bearing types or distance covered. That would then show the results. Applying the same power to the same hill will get you the same results.
No it isn't going to be the same. Because 300W is the input power not the output. Exaggerate it to the extreme, have a bearing made of velcro or sandpaper. 300W into the pedals might be 100W at the chain.
wouldnt it be better if you triggered the crankset w/o chain with a fixed weight if you want a more accurate measure based on time and/or number of crank rotations ? Still, thanks for the work on this... nice
Try your gear in the rollers as well and then look the improvements. Also the road test is good, but the watts gaied must be seen not feel. So in or4der to know them I think indoors is the best way before going on the road ;)
Great show, man. Top gains for me: form - form - form, tight rider with heads down. Another marginal gain to consider: clothing - aero efficiency jersey and shorts.
Tell me you don't understand the data, without telling me you don't understand the data.
Nice work. Congratulations for your initiative and video.
Smoother, less resistant drivetrains will always offer better performance.
Michael Hutchinson figured he'd gained nearly zero with ceramics, after spending wads of cash. And he was a guy who considered shortening his collar bones to reduce his wind resistance.
In your race cast videos, which are awesome, how do you get your power metrics up superimposed on the screen? Have you ever done a 'gear' video?
Fill the ceramic one with sand and do it again.
you need to look at the bigger picture ride for a century with a standard BB on a smart trainer then repeat with the new BB then ask yourself, " do you feel just as shattered this time or do you feel like doing more miles
I suspect the more notable difference between them would be after 5000 miles the ceramic will be like new still.
Nope, exactly the opposite
As I read in all the other comments, you could have avoided some variables in these tests but still, thank you for the video. As for the sand in your bb area, it comes from the holes for your derailleur cable. I have the same issues with my bile, the way to solve this is to go with DI2 since you can have a better seal with a wire.
An ideia! next time you can measure the wind? By the looks of it the super expensive ceramic BB does not worth the price/gain
As you noted, I bet new versus old contributed, to some extent, to those "gains."
funny!....some egos got hurt with the test...LOL.
We just need Mr. Musk and his rockets in a bike forum...lol
Dude this is a great fucking channel. Chapeau!
Thanks bro! I try to make it DOPE AF
I have Kogel Ceramic Bearings BB and pulleys on all my bikes. I love them, smoother than standard bearings.
Does it matter where you measure your power?
Great vid! Looking forward to the similar videos.
You should also compare prices between the stock and the premium product that you’re comparing. You know to make it more realistic.
so like no differnce, 3-5 sec (on 13:30 climb) sounds like measurement error ....
You should do a test at 400 watts for bigger difference when it flex more the axel
Dude, it doesn`t matter what kind of BB you`ve got if you spin the same 300w @99rpm = the same time. Theoretically you should feel spinning 0.0001% easier on ceramics and save some energy that way:)
Bro nice try but you need a controlled environment. Get on zwift and do a lap with stock and ceramic. Same wattage. Just do 200 watts and have someone else set their weight to the same height and weight and same trainer: then ride at 200 watts :)
Haha I said 200 because it’ll be easier to find more people who can do 200 easily.
Did you factor in the your hair growth? This may have effected the second test because of wind drag within the helmet, as well as on your arm... Hopefully your legs were shaved during both tests
did you weight your body before the ceramic climb? Is it possible that this made the defference more than the wind?
This is the opposite of a scientific experiment.
Good video thanks for posting mate. Ceramic is superior over steel, its just smoother and feels better. I tried to do the same test, and ceramic is so smooth I believe that over a long ride you benefit more.
Go full tech if you are a racer that wants to win or you are an overly rich person. Otherwise, an Ultegra line road bike it's enough to enjoy the life of a biker. Just enjoy the ride!
I feel my BBinfinite bb and jockeys wheels get me up to speed quicker, it’s only a feeling. It feels faster smoother.
I believe good bearings will make an even bigger impact in the wheels.
I would love to see all a ceramic test.
Not really but a Vegan Cyclist video will 😉
Why does it say "this is not an ad" in the beginning of the advertising?
So basically your trying to do science, unscientifically. As an engineer, I kind of cringe at all the variable that were uncontrolled, how you tried to draw conclusion that simply can't be drawn from the test. I also think your going to find you will almost always "prove" whatever your preconceived notion is with this kind of testing, because it too easy to make excuses for why number didn't turn out the way you thought they would. I.e. blaming the weather. Good attempt, but in the end, I think this failed to prove anything, and there is a reason you control variables when conducting experiments.
Jake Riddel calm down bro. He isn't trying to solve world problems. Just an awesome guy who loves bikes. It's entertainment just enjoy it.
I'm calm. Big fan of this channel. I just think this is a miss.
Xgalvan1 you're too calm. His opinion matters as a UA-camr and an influencer. His faulty science is only going to benefit the ceramic bearing scammers which is not cool bro.
i kind of cringed too. but his purpose is clear. he wants "real life" results, which we can relate to, and not do real science. the lab results are already known, and it would be pointless if he tried to test it in a proper scientific way. i still think the traditional "control all variables" approach is better for understanding how things work, but his approach is also interesting to show how those known results apply to real life with uncontrollable variables, and how much do those uncontrollable variables matter after all.
i agree...it's like GCN
But on on those hills your cadence will be slower than normal so you won't take full advantage(if any) of the ceramic BB. To isolate the variables you should test it indoor anyway but on an outdoor environment a high cadence flat course would be a better set up for this equipment. Just my 2 cents. Cheers.
Would love it if you tested Ceramic Speed's "Save 10 to 16 watts with CeramicSpeed" claim ;)
What was your bodyweight pushing 300 watts over that time period? Geez.... Maybe because I'm over 50, my FTP power is 220 on a good day, 18 mph avg on a 50-miler on a 168 lbs., 5' 7" frame
By keeping the watts and cadence the same your speed would be identical apart from external sources, wind etc the BB would make no difference except from the lesser friction would reduce fatigue, the only way to test would be to keep the wattage the same and you should see an increase in cadence over a long enough distance.
chris cole this.
This isn't true. the ceramic bearing (and other drive train upgrades) serve to transfer the power (measured at the pedals in this case with his powertap pedals) more efficiently than stock parts. the stock BB might have caused a 3-5w decrease in power transfer efficiency due to added friction, lower torsional stiffness, etc. The cerimic bb might only cause a 2-3w decrease in power transfer. it's all about how many watts make it to the rear wheel when it comes to drive train improvements.
His cadence has nothing to do with it. to truly illustrate this, imagine a drivetrain made out of stone and wood with really rough parts that don't spin easily. a person could theoretically jump on that bike and pedal at 300 watts at 100 rpm, and only about half of his power would make it to the rear wheel, while the other half of the power he is outputting would be lost it simply overcoming the lack of mechanical efficiency in the system. stick nice machined aluminum and steel parts with bearing on there and one could pedal at the same 300 watts at 100 rpm and something like 92-95% of his power would make it to the rear wheel.
chris cole Wait, power is torque * cadence. The BB will reduce torque, so for the same cadence at the same gear, wattage should go down. So, at the same number of watts, you can push a harder gear with a better BB.
chris cole You're misunderstanding the difference a more efficient BB makes.
Lucas Weitzendorf Exactly. So at the same wattage, more of that wattage is being used to turn the wheels rather than produce heat and sound etc