why not more sealed components
 

So you can buy sealed BB but how come there arent more sealed items such as hubs, pedals and headsets?

Note: to me sealed just means I dont have to adjust the tension etc.

Hmm???

Pedals are sealed now a days.

Hubs area sealed too, well the ones that use sealed bearings, if you have ball bearings in your wheels probably u have issues setting up the cones but pretty much if the wheel is ok and the cones are ok u dont need to adjust them maybe each 5 or 10 years.

Headsets use sealed bearings, they need to be adjusted to take the play off the fork, even with motorcycles u have to do the same.

etc???

OP:

Do you mean sealed "CARTRIDGE" bearings? The kind you finger torque down, then fix with another nut and voila... it's smooth as silk, a bit stiff maybe due to viscosity and seals touching, but super silky smooth?

The main reason few manufactures make this is cost. You need precise CNC machines that start with precision molded and cast parts. Gotta have tight tolerances to allow for a smooth press fit without any play, but not be too tight as to cause the bearing cartridges to bind. With cup/cone hubs, BBs, etc., there is more tolerance for spacing, and imperfections in metal surfaces. Just try out a new Shimano Deore or Tiagra hub. Feels rough, not silky smooth. Ride on that hub for about a week, and then feel it. Smoother. The bearings will wear a small groove in the cups and cones and flatten small (i.e. tiny) imperfections. And most of this is inconsequential to overall friction, which the sealed cartridge bearing unit probably has more of, because it's internal grease and seals exert more friction overall.

I am old enough to remember when sea;ed cartridge bearing components were only sold at the highest levels and now it seems that more and more companies are offering cartridge bearings in consumer grade products because the machining costs are less and this is less complicated when you compare it to making a premium quality cup / cone assembly.

Regardless of type... the bearing assemblies we use today are all made on automated machines in large numbers while there are a few small shops like ours that hand build things like hubs and some bottom bracket assemblies to very high tolerances.

A conventional Campagnolo headset is a work of art and then you have things like the Stronglight A9 and a few others that use needle bearings to make them the smoothest bearings you will ever use... wit regular service these will last one a lifetime.

But a decent cartridge bearing will offer as much performance as anyone needs, require less service, and have an exceptional service life... and now they cost less.

Shimano makes conventional hubs because they have been making them forever and have covered their tooling costs many times over but if they were a start up I would bet a dollar that they would be offering cartridge bearing hubs.

I come at this from the perspective of a machinist and if I was going to build my own headset or hub would design it to use cartridge bearings which I can buy rather cheaply while the base would be easier to machine and would not require the same degree of work and hardened steel you need for machining bearing cups which also adds to the tooling cost as you need better inserts.

When I am teaching classes on things that involve bearings and talk about pre-load always point out that better quality loose bearing assembles are far more sensitive to being mis-adjusted than lower quality parts.

A high quality non cartridge bottom bracket is a beautiful thing as it will run more smoothly and has better bearing support than a cartridge that uses smaller bearings... but when you get parts that are this precisely made they do and did come at a premium price and for < 30.00 you could plug in a cartridge bearing unit.

NB , in places like Hubs, sealed cartridge bearings are made in radial,
and angular contact, so they can be adjusted like cup and cone bearings,
but the grease is captive between the seals..

generally radial contact are used because they go in either way up,
so factory friendly. assembly won't need anyone watching the orientation.

I have a couple different Platform Pedals with sealed cartridge bearings ..

and a new pair that dispense with bearings , for an engineered plastic bushing.
they're Excellent... slowest rotating bearing on the Bike.
hubs and BB and Headsets , are all on the market . Have been for quite a while..

intriguing i have never heard of these cartridge bearings... but they sound intriguing!

You can see the prices on sealed cartridge bearings here and that most are inexpensive and swapping them out is relatively easy.

http://images.jensonusa.com/225/bg/bg409a22_____10.jpg
http://www.jensonusa.com/store/produ...e+Bearing.aspx

Bicycles are one area where cartridge bearings have not yet become the dominant system whereas most industrial applications use them... a word of advice is to ignore the hype or anyone that tells you that ceramic bearings are superior as they have no real benefit on a bicycle and cost many times more than steel bearing systems.

I work with a builder who has been building cartridge bearing hubs for 30 years and would say that most of those hubs are still in regular use and we never get warranty calls on them as they just keep going.

We use a high grade bearing and grease that should not need servicing for many tens of thousands of km.

Such bearings have been around for almost as long as any sort of sealed ball bearing. Google for "angular contact ball bearings" or look them up in an online bearing catalog. Tapered roller bearings fall under the same two axis load bearing design as well. But we don't use such things in bicycles because we don't need the extra load bearing ability. And they are also a hair more draggy than pure ball bearings.

For more than 99% of cyclist sealed bearing are better. Almost all sealed bearing are of good or excellent quality, and last a long time. And the thing is the ave cyclist ignores bearings until they fail, and a sealed bearing will out last open cup and cone bearing, since they keep dirt and water out.

Cartridge bearings used to be only for top of the line model components. I would say anytime you can move over to cratridge bearing components, it would be good. Some C&Vers still insist on loose bearing components as they feel that they can better adjust the bearings for best performance than what you can get from cartridge bearings that do have just a little bit of drag from their seals. They also feel that if they service the loose bearing enough, they can make them last much longer than cartridge bearings. The jury is still out on these theories on which approach is really better, but if you want to ride more than service your bike, you should really try out cartridge bearing equiped components. At least with Cartridge bearings, when they do wear out, it's just a matter of replacing them with either a whole replacement component or just press in new cartidge bearings..... no adjustments, major cleaning and new grease needed, just plug and play.

Chombi

Sealed bearings vs cup and cone loose bearings
 

I agree that for 90-95% of riders the "sealed bearings" are a better choice for bottom brackets, hubs, etc. I happen to be in the minority. The caveat is that a WELL ADJUSTED loose bearing hub has less friction. That said, poorly adjusted loose bearings can be anywhere from just more friction to destroying the bearings and cups entirely. Since I have figured out, through years of trying, how to adjust cup and cone bearings properly, I take pleasure in feeling a perfect, tight but free, wheel bearings spinning in my hands. If you don't want to take the time to do it right or pay someone else, then use sealed bearings. They are pretty much stupid proof.

BTW, "sealed bearings" are not actually sealed but have tight dust covers that keep the lubrication in and most crap out. However, as many mountain bikers can attest, it is still possible to get crud into sealed bearings and grind them until they need replacement.

200k

I guess I'm also in the minority. My favorite bottom bracket is the D-A 7700 cup and cone. It's a work of art.

+1 200k, and further to his BTW, that 'sealed' bearings that have been contaminated are far harder to service than loose balls.

Also, the loose ball system uses less steel.

Oh yeah...
http://bikeforums.net/attachment.php...hmentid=222360
Proper.