How good are new bearings

[JosephS]

Before I hijack another thread I was curious about Ball bearings.

They used to be a very expensive upgrade and now they are a commodity. It's actually cheaper to get avid bearings vs associated bushings.

I know that there are steel bearings, carbide bearings and partial ceramic bearings. As well there are greased vs oiled.

It seems that there isn't much of a difference between the partial ceramic,carbide and steel bearing. I was surprised that steel bearings last the longest since the ball races and balls wear at the same rate. Ceramics balls wear down the ball races faster in partial ceramics.

I've also seen that oiled bearing spin so much freer than greased that I have taken to de-greasing and oiling my bearings.

I have seen a few brands knocking around here each with different levels of bearings

Avid- Offering the $1 a piece bearings at the low end they also offer higher end bearings

ACER- I have seen some people here getting the higher end ones and being happy with them.
They also offer sport bearings for about $1.20

Boca- Old school that offers sets from $1.75 a bearing to $8.75

How do these stack up against each other? Are the ACER ceramics the same as Boca for rc cars at 3/5ths the price?

Are the low end Boca bearings better than the $1 AVID bearings?

Where do the vintage AE bearings sit in the pack? I have some of those NIP

I've mostly purchased a bulk amount of AVID bearings so I always have a fresh bearing for any build. I wonder if there is anything I'm missing out on.

[juicedcoupe]

For the average rc car user, high end bearings will just make your wallet lighter. A back yard basher will never see the difference.

If you are racing at elite levels, the minor gains are probably worth it.


Now, I'm not saying to buy the cheapest thing you can. There is a reason that those ultra-cheap bearings that you see on Amazon and Ebay are priced that way. They are likely seconds.

For my rc's, I buy Fast Eddy, TRB, Avid, and Acer. I also buy lots of new takeout Tamiya and Traxxas bearings on Ebay.

[JosephS]

I'm just curious how things overall compare. For me oiled bushings are just fine. I can always just put in a bigger battery and hotter motor.
Are any bearings made in the USA/Europe anymore?

[JosephS]

Also what about the associate 68xx PTFE bearings vs the65xx (sub thousand) metal shield bearings

[juicedcoupe]

Also what about the associate 68xx PTFE bearings vs the65xx (sub thousand) metal shield bearings

In general, PTFE shielded bearings fall in the middle.

They seal better than metal shields but slightly increase drag. However, they don't seal as good as a rubber shield.

Teflon seals are less durable than either, so I definitely wouldn't put them in the wheels of an offroad car.


I believe that Avid makes a bearing with metal on one side and rubber on the other, allowing you to place the rubber shield on the external side.

[b027]

I'm just curious how things overall compare. For me oiled bushings are just fine. I can always just put in a bigger battery and hotter motor.

Bushings always bothered me because they eventually get sloppy. I like how bearings allow higher tolerances to be maintained. Plus lower friction means efficiency and less wear on parts like gears and drive cups…. I suppose if you’re not running much it doesn’t matter. but I appreciate the engineering aspects, and given how expensive they used to be I personally find it a very satisfying upgrade to a well built model.

[Frankentruck]

There was a guy I was buying parts from that was trying to convince me that bronze bushings were better because he had experience with bearings seizing and transmissions getting destroyed under load. I've never had that experience but I've had worn bushings allow parts to get sloppy and wear funny. I guess worn bearings could get sloppy too. I used to have some that has lost their side seals. They needed constant lube and cleaning, but when clean they were super low resistance.

[juicedcoupe]

There was a guy I was buying parts from that was trying to convince me that bronze bushings were better because he had experience with bearings seizing and transmissions getting destroyed under load.

I have a Thorp gear set and Trackmaster input shaft that were damaged my a bearing failure. I received the car like that, so I don't know how much it was driven after the failure.

I was able to glue the input shaft and drive pinion back together but they had completely lost their press fit.

[Lowgear]

Due to my puller builds, I became pretty obsessed with bearings in my quest to use the best of everything. What I found is that there are American manufacturers that still produce miniature bearings, but with a catch. They either don't sell to the general public, or you have to buy in large quantities. So your only choice is to hope a distributor stocks what you need, or that they appear on eBay one day. It seems like other reputable countries that produce bearings such as Japan, Germany, Switzerland, France, etc... follow the same rule. The company names brought up in this thread are just distributors that sell Chinese bearings which are likely all produced in the same factory. The rest is marketing. Not that there's anything wrong with that. Go with what's the most convenient for you, and offers the best customer experience.

When it comes to our R/C usage, I've always read that pretty much anything is sufficient. The reason being is the stress our models put on bearings is way under what they're rated for, so it doesn't really matter that much. I believe the majority of bearing failures we experience are due to side impacts. Radial bearings have poor axial (thrust) load capabilities which knocks the inner race out. Deep groove radial bearings help alleviate that problem but again, not really needed for R/C, and their increased resistance as a result defeats the benefit.

As it pertains to the various shield types, we normally use either rubber or metal shielded. Rubber for dirty applications, and metal for clean applications. There's hybrids like juicedcoupe mentioned that Avid sells called 'Revolutions' which have a rubber shield on one side, and a metal shield on the other. The idea is that it should give slightly less resistance as a result than a full rubber sealed bearing.

[b027]

When it comes to our R/C usage, I've always read that pretty much anything is sufficient.

"sufficiency" is a good choice of words here - both work and which is better can be subjective. It helps to consider the goal vs tradeoffs.

For example: stock vs modified motors - I imagine few would prefer bushings in a motor given that high RPMs increase sensitivity to friction and heat. In low speed applications like wheels and axle carriers, heat is much less of a concern but friction still matters! As above I personally prefer to run with higher efficiency for maximal component longevity.

I believe the majority of bearing failures we experience are due to side impacts.

this makes sense to me. I'd suggest installation issues contribute as well, for example when force isn't applied evenly (or with the right tool) to the races, or when the bearing isn't seated properly in a high-tolerance application. Bearings thus require more care and have higher assembly tolerances, while bushings can take more abuse.

A related thought is misaligned bushings can be broken in somewhat, whereas misfit bearings will just bind and wear, possibly leading to more significant problems in other parts like gears. I had a Traxxas transmission once that required significant shimming of the case to make the stock bearings fit without binding. Bushings probably could just have been "run in" with use and been acceptable, but the bearings needed to be addressed.

As it pertains to the various shield types, we normally use either rubber or metal shielded. Rubber for dirty applications, and metal for clean applications. There's hybrids like juicedcoupe mentioned that Avid sells called 'Revolutions' which have a rubber shield on one side, and a metal shield on the other. The idea is that it should give slightly less resistance as a result than a full rubber sealed bearing.

Anecdotally, when I was younger I used to do a lot of high-speed rollerblading and we always pulled the shields, cleaned and freshly oiled for every session. They were good bearings as I recall (AAAA or something like that), but we wanted lowest possible rolling resistance and this required a lot of maintenance. it was definitely worth it despite the time required to prep 16 bearings each time!! I don't know how much the shields actually mattered and I always assumed our primary benefit came from replacing the grease with oil and keeping the balls and races meticulously clean, but I could feel some difference in hand with and without the shields installed. I certainly notice it more with the rubber shields that are designed to create a better dust/dirt barrier that necessarily adds more friction.