Who /bikemechanic/ here?
I'm trying to replace the bearings in my Mavic hub. These bad boys (pic) are going to set me back about $20-30 since they're such a specific product, but I have a feeling they're identical to a generic 6001 bearing cartridge. Measurements for both are 12x28x8. Am I failing to account for something here?
>>970465
Bearing sizes are standardized. If they're specified to be the same, they're the same.
The only differences are in the materials and tolerances (which directly translates to quality). Truth be told, I can't see much advantage over a generic in this situation. Bicycle bearings are neither under particularly high load nor do they have to spin at very high speeds. I can't imagine there's any noticeable difference between some random, no-name Chinese shit and some >$9000 ABEC-69 wank fodder. The latter might last longer, I guess, but other than that...
>>970470
Thanks! I knew it was a scam.
That said, it's a big pain to change these cartridges. Is some cheap Chinese shit going to last more than 5000 km?
>>970474
Hard to say. LOT of variables there.
If you can find tech specs for them (manufacturers and suppliers list them up front, but some bike shop almost certainly won't), compare the dynamic and static load ratings. If they're similar, I would expect them to have similar longevity; load ratings are tied directly to tolerance and the quality of metallurgy.
If I had to hazard a guess, though, I'd say "probably".
Unless you're a fatass riding with no suspension on a rocky trail, anyway.
nsk, skf, fag, timken, ntn... all of these brands will be cheaper and are all top quality... contact your nearest bearing wholesaler. but be warned aftermarket or generic may not be much cheaper than you think. just wont be paying the bike dealerships middle fee
![FAG-Joplin[1].jpg](https://i.imgur.com/Dl2VS63.jpg "FAG-Joplin[1].jpg")
>>970480
>fag
Gets me every fuckin' time.
>>970480
>aftermarket or generic may not be much cheaper than you think
This is sports equipment. It's ALWAYS way cheaper.
The 6001 size in particular is very common, making it that much more inexpensive. Under $4 to your door (assuming USfag).
http://www.ebay.com/itm/6001-2RS-Sealed-Bearing-12x28x8-6001-RS-Ball-Bearing-QTY-2-/371500439674?hash=item567f26d87a:g:f5gAAOSwBLlVfu5n
Your intuition is correct.
Unless you are buying bearings from a bearing manufacturer or merchant, you are getting whatever crap Mavic could find for the cheapest. You're paying not for quality, but for the convenience of knowing that that specific part fits in that part.
>>970465
>I'm trying to replace the bearings in my Mavic hub. These bad boys (pic) are going to set me back about $20-30 since they're such a specific product, but I have a feeling they're identical to a generic 6001 bearing cartridge.
they *almost* certainly are the same as generic cartridge bearings of the same size in the same material.
Bicycle/bearing general info-
1. the four main bearing materials are carbon steel, stainless steel, hybrid-ceramic and full ceramic
2. carbon, stainless and full-ceramics have the balls and races made from the same materials. hybrid-ceramic has ceramic balls and stainless races.
3. Hybrid-ceramic bearings don't cost much more than stainless, generally. this is because the races are the expensive part of full-ceramic bearings. the ceramic balls are relatively cheap.
4. hybrid-ceramic bearings aren't as efficient as full-ceramics, but then again, the full-ceramic real-world advantage is pretty small. Full-ceramic bearings *feel* different tho because they are more rigid--and the (knowledgeable) belief is that people associate that ride feel with better efficiency.
For a single China generic 6001-size cartridge bearing, carbon steel might cost $8, stainless-steel might cost $12, hybrid-ceramic might cost $16 and full-ceramic might cost $120.
in the USA, a company named ABI markets a line of hybrid-ceramic bearings for bicycles. Jensen USA lists some ABI hybrid-ceramic 6001's for $17 each. see Google for further buying info
continuing in next post....
>>970649
(more blathering...)
Further myths busted-
Engineering references generally only recommend full-ceramic bearings for very high RPM use--such as, 25K rpms and above. There is no use in a bicycle which really demands ceramics at all.
Full-ceramics normally aren't used in large and heavy equipment, since they tend to chip when subject to shock-loading. This has not been observed to be a problem with bicycle use however----even MTB use.
If you run stainless, hybrid or full-ceramic bearings in a bicycle--AND they have removable rubber seals--then you can also use powdered teflon instead of grease. The powered teflon has lower rolling resistance than grease. You can buy it online from a place called Spurlock Tools.
....You can't use teflon powder with shielded bearings because the metal shields get bent up when you pry them out. The rubber seals you can carefully pry out and then snap back in afterward.
....And you can't use teflon powder in carbon-steel bearings, because they need some kind of oil or grease to keep them from rusting. The teflon powder will drive out the liquid oil if you combine the two, and the carbon steel bearings will then rust from atmospheric humidity. Stainless and ceramic bearings don't have this problem.
My own opinion: I don't think you'd see a great difference with any of the four choices, really. I've never had any ceramic bearings in any of my bikes.
There is some research that shows that hybrids have faster wear rates than the other types and that for the longest possible life, the balls and races should be the same materials. This hardly matters for a bicycle wheel tho. If the bearings wore enough to get even a tiny bit loose you would notice it in use, and replace them anyway.
>>970465
I used fag calculator just for fun. I chose ridiculous loads for one bearing: 100 kg radial load and 20 kg axial load. Which is unrealistic to achieve. Now, if you drive at 100 km/h you should be able to ride for ~3000 hours...
>>970470
Yes, in most cases generic bearings perfom the same.
In high end hub ceramic and hybrid bearings are used to reduce the friction of the bearing, but just that.
In BMX they use quality steel bearings because they resist better all the jumps and that.
