Lets assume, for a moment, the data on this website is correct
Ceramic Ball Bearing vs Steel Ball Bearings
Now, lets say you're steaming down the road at 55mph with my wheel set (approx 24" diameter).
55mph is 4840 feet per minute and the circumference of my tires is ~6 (2ft*3).
That means, at 55mph, my wheels are rotating at ~806rpm
Lets now say 70mph - 6160 feet per minute which comes to 1027rpm.
The knee on the steel ball bearing doesn't occur until nearly 4K rpm - and the knee on ceramic doesn't happen until ~6K. Divergence between the two graphs doesn't really start to happen until 2K (really, probably not 2.5-3K).
Ceramic bearings shine in two areas
1) High Rpm
2) Longevity (mostly, at high rpm) - harder bearing
3) high temp operation
4) corrosion resistance
This is a case where yes, there will be some reduction. However, potentially not measurable and cost v. benefit is significantly out of proportion. Bearing losses are a somewhat significant portion of rolling resistance, but it looks like you're not going to find much reduction from ceramics.
Just for fun, any race car going 200mph (lets assume my wheels as I don't really know what diameters are used)
200mph = 17,600fpm... Wheels are rotating at 2933rpm.
So yes, ceramics look like they could be useful. Especially if they get hot due to heavy brake usage more common on a track versus on the road.
Oh, and I'm not saying you shouldn't do it... I'm just saying that these aren't the droids you're looking for.
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Yes, those are back of an envelope calculations and I'm well aware that pi!=3
