Whats good about a good hub vs a not so good one ?

[jcole]

I often read conversations on the mtnbike forums about lacing up your rims with a good hub, or how a wheelset will be stronger or less prone to getting flat spots if using a good hub.

Can someone explain the mechanics behind this ? As I see it, a hub is a chunk of metal without much room for flexing. One may be lighter than another, or have a stronger axle inside, but I don't see what the big deal is other than weight.

So can someone learn me how hubs are important ?

[SammyJ]

So far as I know, 20mm front hubs don't vary that much, 'cept for weight as you said. There have been some hubs manufactured that were weak near the spoke holes though:



Rear hubs have freewheel engagement mech, which is where the big differences come in. Loads of different engagement types are available, each with its pros and cons.

[biggles604]

Originally Posted by jcole

So can someone learn me how hubs are important ?

No, but I can teach you .

I don't see any way that a hub could affect wheel strength unless the holes were incorrectly drilled, which with modern CNC isn't likely.
The biggest difference with cheap vs expensive, is the precision of the machining. A quality hub will be really precise which will lead to longer bearing life and be easier to service and change out bearings. On a rear hub, the free hub mechanism will be more precise which means less wear and a stronger interface, with better ease of service.
Also, bling hubs tend to be lighter.

All said though, the quality of cheap hubs has progressed so much in the last few years, and some of the mass produced hubs are of a really good quality for very little money.

[ESHER SHORE]

a good quality hub (for example a Hope Pro II or Chris King ISO disc) will run very smooth because its well machined and has good quality bearings made to high tolerance (often ABEC rated)

an important factor with a hub is whether replacement bearings can be sourced once the bearings are worn - especially for hubs using sealed cartridge bearings which sometimes come in bizarre package sizes which are not always available locally from a bearing supplier


in terms of wheel strength, the drilling tolerance of the spoke holes actually has a big effect on how well the wheel builds - for example King hubs have very tight tolerance spoke holes and can be quite tricky to lace and tension as the spoke tends to drag whilst being tightened - which makes the wheel harder to build, but also makes the wheel stiffer because there is less movement within the spoke lacing

another factor is that larger diameter hubs (often called high flange) can produce a stiffer wheel relative to using a small diameter hub as the large diameter hub uses shorter spoke lengths, which is turn gives the wheel less flexure and allows more tension to be put into the wheel during building

I build alot of wheels at work, and find the Hope Pro II a good hub to build with in terms of ease of lacing, length of spokes and smooth running of the finished wheelset, and ease of replacement of bearings and the freehub mechanism

[shirk]

What hub is that sammyj?

[SammyJ]

That's a Campy C-Record, ala Sheldon Brown.

http://sheldonbrown.com/harris/record-track.html

[heckler]

when I had Deore hubs, the bearings would get dirty (grinding when the wheel spins) within a month of wet shore riding, and I'd have to overhaul them (clean, grease, and replace ball bearings), and the free-hub body (the clicky part the cassette attaches to) would need to be replaced annually

when I was running XT hubs, the bearings would last a few months before needing service (clean and grease), and I don't remember having to replace a free-hub body.

With my King hubs now, I get them cleaned once a year, but only because I want them to last forever, not because they need it.

It's worth it in the long run to buy good quality hubs, and take them from one bike to the next. Same deal with the head set.

[Tom]

Weight, as well as engagement (in the case of rear hubs).

[biggles604]

Originally Posted by ESHER SHORE

a good quality hub (for example a Hope Pro II or Chris King ISO disc) will run very smooth because its well machined and has good quality bearings made to high tolerance (often ABEC rated)

Only partly true. If you put high quality bearings into a low quality (Poorly toleranced) bore, then they can be loose and have play, be off centre from each other adding a non-axial force, or be too tight and crush the races leading to premature wear. Also, a high ABEC bearing isn't necessarily a good choice since it's going to be harder (for the higher precision), therefore will lack the impact resistance of a softer, springier metal. I would suggest ABEC 3 or less. Better yet, use a full complement bearing like the EnduroMAX for a larger surface contact area.

[BrownBear]

Originally Posted by heckler

It's worth it in the long run to buy good quality hubs, and take them from one bike to the next. Same deal with the head set.

Don't headsets get severly damaged when you pull them off the frame?

[Bicycle]

For a bmxer a good hub will make them coast in the park forever. And clicky hubs are sweet lol.

[biggles604]

Originally Posted by BrownBear

Don't headsets get severly damaged when you pull them off the frame?

Not if you do it right, but every time you remove a headset it wears the cups and the frame slightly, so after a while, the tolerance will be out and it will not be a press fit. That's why I don't understand the people who buy a CK for life. Buy a headset for a frames life instead.

[Bryce]

spending more for a quality rear hub makes sense but not for the front. Its basically a piece of metal with a hole

[huckit59]

its like a wife vs mistress they will both do the job but one will be more enjoyable

the wife will work but after some use you will have to clean, cook, walk the dog, etc

with the mistress it will be better engaging and you will be able to only play with her when you want to plus they usually are pretty sexy ant when you have to do anything such as clean cook etc it will be more enjoyable because all the parts are how they should be nothing is sitting loose