https://www.fasteddybearings.com/8x22x7-bearings/
prob not the nitride shit but their regular 2RS bearings kick ass
Probably good for like pulleys on stepped shafts
The white ceramic is aluminum oxide (Al2O3), and the dark ceramic is silicon nitride (Si3N4)
Silicon nitride seems to meet or exceed aluminum oxide mechanically in most ways (tensile strength, compressive strength, fracture toughness, youngâs modulus). Itâs also, predictably, more expensive.
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No shit man.
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As we move towards 10mm axles becoming the standard, do you think 6900 bearings are good enough for wheels or is there enough benefit from a larger bearing diameter to justify future wheels having cores that accomodate those bearings?
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I shit you not brada
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These contain two conical needle bearings, like old land rovers and trucks do (i think back in the day all cars had these). They are very robust and nice, but dont like high rpms. So pretty much perfect for pneummies and mountainboards.
The bore on the core being bigger I think would be a benefit in being able to get a tighter fit for the bearing. Slop between the bearing and wheel sucks.
The loss of efficiency from a larger bearing is small and then again give it some miles and contamination and bet the larger bearing has less friction than the smaller with the eventuality being the smaller is so damaged and grinding itâs trash.
Thereâs no other benefits I can imagine for a smaller bearing other than a bit less weight and requiring a hair more force to get them rolling.
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Iâm not sure I agree with larger bearings having more rolling resistance. I thought rolling resistance decreased with diameter. They have more mass per surface area, so might have lesser initial acceleration.
Personally i ride Hybird Ceramics - on fronts and Hubs. with a slight lube for noise (they are pretty silent) and ive had one ball blow out on a front wheel, which was⌠challenging to recover from at 50kph (was like hitting a bump you dont see)
But i also thumb remoted that wheel 10km ealier into a curb.
So far otherwise 6000km and rolling smooth. (having good spaces, such as Sesismic Tektons have helped alot)
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Keep in mind if the Slicone nitrade ones where the ones that broke,. they must have taken some kinda extreme blunt force truama or QC check.
Would never run whites.
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I wouldnât expect you to take my word for it, but how about the word of the engineers at SKF, whose job it is to know all about bearings?
An excerpt:
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Noooo, donât post equations, math bad intuition good
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Angular contact (Kaly bearing) vs regular 10mm axle bearing. Iâm a big fan of the angular contact bearings.
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Can you explain how this makes your point? There are several bearings that use 6 larger balls instead of the standard 7. These must be slower�
My point is that larger bearings (larger bearing mean diameter, which is the middle between the ID and OD) have higher rolling resistance than smaller bearings.
The diameter of the balls doesnât matter for that, because that doesnât change the mean diameter.
The diameter of the balls does matter for other things like the load rating, because bigger balls can handle more load.
In any case, going from a 608 7-ball to a 608 6-ball might net you some reduced friction from grease viscosity, but at the cost of some durability and load capability, because there are fewer balls to distribute the load (even if they are slightly larger).
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6000 bearings would be much better than 6900 bearings. 26mm OD, width 8mm, vs 22mm OD 6mm width. I personally feel 10mm axels should become standard for Esk8.
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Yeah, Iâd also like to point out that all this talk about bigger bearings having more resistance, probably doesnât matter much at all in the esk8 world.
In regular unpowered skating (be it rollerblades, longboards, regular skateboards, whatever), youâre very much more aware of tiny energy losses like bearings or wheels, because youâre working with less energy, and itâs all coming from your muscles.
In esk8, you have a fuckoff big energy source thatâs not powered by your muscles, so it doesnât matter nearly as much. The losses are still there, but they are less significant in the overall picture.
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Make bearings? That sounds hella hard and beyond simple machining. How do u even make a hardened metal ball? The designing part sounds easy in comparison.
I did the google search: https://m.youtube.com/watch?v=41Z5v4NybWA
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Lol, I was not talking about making bearings. I was suggesting that hubs and wheel cores be made to accept 6000 series bearings. 26mm bore, 8mm deep.
Just slowly move away from 8mm axels altogether
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