Bad bearing source? Check your new bearings.

[Frankenstein]

OK running after some old gremlins in the basement I came across this bearing that seized in my motor. It's a main bearing marked 6202z and then the letters NGY...

Now these are the same as the other 2 I bought, which also seized... Don't want to point fingers, but I got them from bicycle_motor_works on ebay. These bearings only bother me because doing a search for the Ngy bearing company literally gives no results.

Except for a small number of Russian websites and motorized bike catalogs.

The listings for that motor state the bearings are ntn, nsk, or Ngy. Now nsk and ntn are large known companies that even found time to build a website.

The owner of Ngy didn't even do a website yet... Or at least not by Google's eyes...

So nameless Chinese bearings end up in motor and die twice in row.

If you see these put them in the junk drawer for something else, just in case.

 

[Frankenstein]

Oh and I remember ordering a set but never used myself, gave to a friend for his engine, funny enough I think his seized too in the main bearings...

 

[DuctTapedGoat]

Oh and I remember ordering a set but never used myself, gave to a friend for his engine, funny enough I think his seized too in the main bearings...

I would suggest to find something aftermarket, maybe German or swiss,

I've never rocked a main bearing before, so I dunno what would replace to that yet.
I would avoid that number series that looks like BOZZ stock and have something aftermarket from industrial suppliers and/or imported before I put another same thing in there.

Everything is obviously manufactured to a 10krpm standard so maybe a higher rpm standard bearing will have more longevity.

 

[butre]

I use a FAG 6202-C3 main bearing. made in germany, high quality stuff. 12 bucks a side after shipping, but better than having to walk 10 miles back home because the cheapo chinese bearing crapped out on you.

here's the specifications on those FAG bearings

 

[Frankenstein]

I use a FAG 6202-C3 main bearing. made in germany, high quality stuff. 12 bucks a side after shipping, but better than having to walk 10 miles back home because the cheapo chinese bearing crapped out on you.

here's the specifications on those FAG bearings

Definitely worth a look, really putting a no-name bearing in an engine is probably as bad as getting a no-name engine kit, you really haven't got any idea if it's going to be total utter crap or half decent, but chances are you won't get lucky.

Still, had these bearings fail multiple times, and I'm not the only one, meanwhile butre is using real quality bearings and doesn't seem to have anything bad to say of them. Likelihood of the Ngy bearing company producing s**tty bearings is pretty good based off what I've experienced, and since I still can't find an actual company to go with the mark it's probably best to avoid them.

 

[DuctTapedGoat]

Everything is just a series of Production Number in the grand grand grand grand scheme of it all.

 

[butre]

Everything is just a series of Production Number in the grand grand grand grand scheme of it all.

bearings are standardized commodity products, you can get an SKF, a FAG, a Koyo, or even a cheapo chinese turd in the size you need. just the cheapo chinese turd isn't going to be as good as an SKF or a FAG, the precision grinding won't be quite so precision, you don't know how it was stored before being shipped out, and you don't know if they were properly hardened before assembly.

 

[Frankenstein]

bearings are standardized commodity products, you can get an SKF, a FAG, a Koyo, or even a cheapo chinese turd in the size you need. just the cheapo chinese turd isn't going to be as good as an SKF or a FAG, the precision grinding won't be quite so precision, you don't know how it was stored before being shipped out, and you don't know if they were properly hardened before assembly.

Also explains why the good skf bearings I had dropped right in while the Ngy needed something along the lines of a hammer to remove or install in a crankcase...