Equipment Impacting Watts - Ceramic Bearings

In simple terms

Marketing Hype?
or
Valid?

Felt_Rider said:

Although this question may belong in the equipment thread it is actually a question concerning watts and I hope for some responses from those who specialize in this area to the validatity and cost effectiveness of upgrading equipment.

I was in the process of ordering replacement bearings for my rear wheel and during the research for the part number I found a number of articles that grabbed my attention concerning ceramic bearings and watts.

Although I already ordered ceramic bearing replacements instead of the lesser expensive stainless model from Velomax I was wondering if there are more valid studies and if this is a worthwile expense in upgrading equipment as it concerns performance.

I have found several articles like the one attached, but was wondering if others have found real world experience with using ceramics. A couple of articles claim to increase 3-12 watts.

If this is valid I wouldn't mind going ahead and upgrading the front wheel bearings and perhaps upgrading the bottom bracket to something like the FSA MegaExo ceramic BB in the future. Even though I don't officially race I wouldn't mind improving in my rides/training by having a more efficient bike.

threesports.comnewseventdetails.phpOpen ↗

You'd be likely to gain more power by spending the extra $$ on a new chain more frequently.

On the FSA site there is a study quoted that came up with ranges of something like 0.3 to 0.6 watts saving for ceramic bearings (not necessarily FSA ones either since the study doesn't say FSA anywhere, though SKF is mentioned). So possibly if you replaced wheels, BB, pedals and jockey wheels you might get close to 2.5 watts, assuming the gains were additive. But using cheaper rubber seals on the bearings (like FSA uses) can scrub all of that and more right off.

Also many of the hybrid ceramic bearings on the market have ABEC ratings that are far worse than what is available with quality steel bearings and with low rated ceramics you would wind up paying more and losing watts. High rated full ceramic designs are ~$600 a set and up (way up).

Okay, thanks for the response.

My career is in engineering and my educational background was in Industrial Design so it is easy for me to get (distracted) caught up in the mechanics of things.

Based on the articles it sounded reasonable that reduction friction would be helpful, but then again drag from something else (clothing, bottles, etc ) could nullify the small gain by a smoother rolling bearing or a cleaner chain and the $$ spent does not equate to gains unless all areas are covered mechanically and aerodynamically.

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bearingworks.commaterials.htmOpen ↗

http://www.insidetri.com/train/bike/articles/1953.0.html

Okay so maybe I was lured in by some articles stating that ceramic bearings could slightly improve wattage, but since I had to replace a damaged rear bearing anyway, I thought it may be worthwile to give them a trial run.

Unfortunately I did not replace the bearings until after my group ride on Saturday so I didn't get to do a road test yet, but I can tell a significant difference between the old stainless and the new ceramic while on the repair stand. How much difference I cannot tell and have no way to measure. The difference in cost was about $15 more for each of the two rear bearings. I haven't seen the $600 versions, but I believe based on the literature and the feel that the ceramic bearings that I purchased are a very high quality. The rubber seals on these type of bearings regardless of ceramic or stainless do interfere with how the bearings spin. I guess there is no way to solve that problem as the seals are necessary to keep the bearings clean and lubricated. I believe I will upgrade my front wheels this fall or sooner.

Even though it may not be relevant to power/watts like I had asked, I thought I would give an update on this upgrade.