They sit on a small nubs and press in I think.
The benefit to this is that they don’t explode… It will still works even if a few of the rollers fail. But normally they just start to spin slowly and make noise before an actual failure.
The solution is a custom skate truck with integrated replaceable wheel hubs(NOT HUB MOTORS, HUBS)
Actually that’s a very good point, is there any particular reason we don’t use two wedged roller bearings and just keep the wheel core in compression?
Because the wheel cores are not precision enough(plastic). They would have to be custom aluminum precision cores.
I thought tapered roller bearings were pretty tolerant to slight misalignment? That’s a shame.
Although maybe I might go ahead and buy a few, just for the sake of trying it out 
I mean, it’s a bearing so it should be as precise are possible or that will effect the overall life(which is our goal anyway.)
Iv’e thought about using the wheel as the bearing seat, but a hub built into the truck would still allow you to use normal longboard wheels, and not have to replace some super expensive cored wheel every time. it wears out.
Then we can just bolt the wheels to the hub, e z p z.
EDIT: This would also solve this whole axle strength/thickness issue we have been having as well(with the carvons, and hub motors).
Could view changing hub tires like changing ur wheels but not wasting all the inner part which is still good.
Hub motor tires dont need a core and can be inexpensive. It’s less material. I’d have thought they’d need a core but doing well without so far.
I talked to the company that I have been in contact with and they said they are looking at some SS 608 bearings. Where the ceramics that you had explode where they ceramic or were they Silicon Nitride?
White balls with white races (ceramic/ceramic) and black balls with silver races (ceramic/steel). I don’t recall the details but could find out if needed
I was talking to one of the engineers and they had said if it was full ceramic then they could see them exploding. And could even see the ceramic and steel dying because there are varying degrees of ceramic. She said these would be Silicon Nitride balls with steel racers. She also said that if someone ever breaks the silicon Nitride ball to send them a picture and they will send out a replacement. I’m asking abut the grease and the labyrinth seals. Stainless Steel bearings might be what you may be looking for so they don’t rust.
This is what my contact had said
The 608’s do indeed have what are you referring to as a laby seal. What I was mentioning below was that the 608’s do not have the extra inner race groove for the seal to protrude into. So from a sealing stand point, these bearings do a darn good job.
Per what you were saying, blowing up a hybrid bearing (hybrid = steel races w/ ceramic balls), is a bit surprising to hear. This is obviously not impossible, but it would be interesting for us to hear about the circumstances in which this happened. In no way should this be common for any quality hybrid bearing.
Per the salt roads in the winter, this skater is going to have to accept some level of contamination as icy/salty roads melt and this liquid splashes against his wheels. The heavy contact seal (RH), is probably going to be a darn good option for sealing against this liquid for longer periods of time. The RH seal is much different from the standard RS seal (light contact) and is extremely different than the Z shield, which has a gap. Even if this skater would choose a SS option, these harsh conditions are bound to put more wear and tear on the bearings.
All of our greases are more than sufficient for the skateboard applications, even under these extreme conditions. Water has the ability to wash out any economical grease and most non-economical greases. There are options to partially overfill the bearings with grease to help prevent some of the issues this skater is seeing. You would have to know the specific customer order to overfill the grease under specific circumstances, this is not something you want to do as a standard. Both higher grease fill and RH seals (vs RS) will create more resistance after installation and somewhat continued vs. other options. If I were specifically this skater, I would set up my board/bearings for the winter vs. other seasons
So to clarify, am I hearing that hybrid steel/silicon-nitride 608-2RSH filled with grease is the best option?
I’m having difficulty finding those anywhere
I think 608 RH actually 
I couldn’t find any 608-RH (or 608-2RH) – and I could find 608-RSH (or 608-2RSH) but not hybrid / silicon nitride. Any links would be appreciated 
The only thing I found were inline skate bearings.
At what link? As far as I know, inline skate bearings are 608
Yeah. I think it was miscategorized.
Hi-Lo RH Swiss LE. https://www.amazon.com/Bauer-HI-LO-Swiss-608-Bearings/dp/B00AVPI7NQ