This is not an objective statement. Just because you can compensate for friction, does not mean it is acceptable. I, for one, prefer the least amount of rolling resistance possible. Even if it has a negligible difference on range I’d still prefer to coast without it feeling like the brakes are on. Could also heat up the motors prematurely in a high performance application. Similar to overpacking gears with grease. Bones reds properly spaced have never done me wrong.
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yeah I think it does, shipping is still cheap if you buy 3 sets. Doesnt make much sense buying one set though
why is it okay to over pack bearings with grease, but not okay to over pack gear dries with grease?
I use zealous but I have been testing some silicon nitride bearings that I get from a bearing company that I have been dealing with for a few years. They are expensive but with good grease and heavy contact shields they keep out alot of stuff. @b264 had a set for a bit. But I think he exclusively uses bones until the die because they are cheap because he rides in snow and brine and it is a bearing killing combination.
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Silcon Nitride! YESSS!!! The future!
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Is that just the grease inside the bearing?
Must investigate
No it is like a ceramic bearing but without the cheap ceramic that just blows apart in skate bearings Silicon Nitride is harder and more durable then ceramic and there are more regulation to control the purity of it.
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These are kind of unobtanium at the moment. More OEM than a brand…
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In order to actually feel the bearing friction or see any difference in current consumption or range you would literally need to put tar inside your bearings.
Testing how a bearing rolls unloaded is not an indication of drag.
Grease is what should be used in anything other than a single run bearing
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I was looking through Boca bearings because they have some, but fell flat on my face because I have no clue how to correctly search for a bearing based off its dimensions
The interesting thing is that the Silicon Nitride bearings I use have no lubricant in them - they run loud, but smooth and the roll time is insane compared to normal greased bearings.
Would that improve with grease or was it recommended to run dry?
The difference compared to the drag from your drive train is minuscule.
Even for gravity boards there’s a case for ignoring bearing drag, still many people advocate for grease there.
If you want to pay the price for a .2% increase in coast speed then fine , but its not the answer to the “Best bearing” question at all.
No it can’t.
No it isn’t. Bearings are designed to run with grease, they’re designed to run with full contact shields.
I’m not advocating for anything outside of what bearings are designed to do.
Gear cases aren’t designed to be over-packed.
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no idea, haven’t tried yet - I like them greaseless because I don’t have to constantly clean the black crud that seems to seep out all the time.
If you want to talk bearings and which ones stand up to abuse…find some roller derby girls to talk gear with.
My take away from when I’ve talked with them – any high quality bearing will last forever… but only if you clean them regularly.
Also hanging with Roller derby folks is a blast – very fun group, generally.
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In bearings extra grease is more likely to just get flung out.
Very high tack grease might still be an issue, but I’m not sure.
It was my impression that there is more than a 0.2% difference in free-roll distance/speed. Not too sure where you got that figure from. Just spinning a wheel by hand you can see a major difference in roll duration. The resistance from drivetrain is even more of a reason to save additional losses wherever possible. You like contact seal bearings. I like traditional bearings. They both have positives and negatives
So you are telling me, motors that I already overheat under stressful conditions would not overheat sooner while pushing against additional friction? I personally haven’t done the experiments. But since you have I’d be curious to see the numbers.
According to mcmasters, a 608-2RS is rated for 20,000RPM. Playing with the esk8 calc, we should only be seeing 2000-3000RPM so it’s quite within reason. 20,000RPM using 6in AT wheels has an estimated speed of ~360mph. Don’t think anyone is going quite that fast 
Even 50mm wheels has an estimated ~120 mph
Bearing maintenance probably has the biggest impact on longevity. If you keep your bears relatively clean and happy, they should last a long time. The only time I’ve had a bearing failure is due to absolute cheap crap bearings. I’m talking about 15 cent bearings that probably weren’t made with the correct tolerances and exploded after the grease dried out. Even then, they lasted I would estimate 50 miles
Other things to note is genearlly speaking, more balls are better as better load distribution and bigger balls (because size matters 
) are better as less contact wear. Still, in my opinion, the differences are minuscule. I would go with zealous provided that the spacer space is correct. I like the ones on mine
Just spinning a wheel by hand, without any load or other factors is the ideal condition to see the difference.
Hook it up to the drive train, then spin it by hand and see if you can tell the difference between any two bearings. Even with a hub motor.
Yes, if we’re talking about the difference between sheilds and grease.
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