Hub bearings and rain
 

I have one wheel with a standard hub with cone bearings (that came with my Cube Nuroad bike), in good shape (in a sense it doesnt have play), and I open the hub ocasionally, clean everything and regrease (I use lithium grease) and the wheel is fine in the dry , however after the ride in rain, you get this grinding noise from the wheel (when you turn it stationary and listen).

1. do I use the wrong grease (lithium) so the water penetrates?

btw, I looked at the rubber rings on each side of the hub and they should definitely be replaced.

2. do hubs with cartridge bearings withstand water from penetrating better than cone bearings?

Trailer hub bearing grease will stay put pretty darn well in the rain. When I was commuting I repacked the bearings annually, whether they needed it or not, and (just guessing) probably had 30-50 rain rides on them every year.

Shimano LX rubber seals are surprisingly good at keeping the bearings dry in any cloudburst I ever rode through, FWIW. Can't say anything about "cone bearing" hubs in general.

1. - https://www.google.com/search?q=mari...hrome&ie=UTF-8

2. - Depends on the seals in the bearings, but in general, yes.

I have more rain miles than most (10,000+) including downpours and occasional floods.

All my hubs are traditional cup/cone design, greased with white lithium grease, at roughly 5,000 mile intevals. I've yet to experience a single premature bearing issue owing to rust.

The grinding you hear might be grit in the gaps between the moving parts. Even if some grit does penetrate deeper the rolling action will move it of the track where it remains trapped by the grease. (Think of the dirt lines at the ends of windshield wiper strokes).

So I add the OP's concerns to my very long list of things to not obsess over.

The cone and/or bearings might already has very small pits on them causing the grinding sound. It’s happened to me before…that grinding sound. I’d swore they were still good. But, I had to thoroughly clean, and closely inspect them with a strong magnifying glass to see the small pits. Installed new and the problem was solved.
Dan

OP: If you are regularly opening the hubs anyway, you should be replacing the bearings (use grade 25 bearings in the appropriate sizes) and use high-quality grease. If you ride in the rain a lot, use marine grease. I pack my hubs with LOTS of grease, and let the excess ooze out through the seals. More grease = less room for anything else to get in there.

Also, are you really cleaning everything thoroughly, using degreaser or at least isopropyl alcohol?

And yeah, replace those seals.

If you don't like the maintenance, then yes, cartridge bearings can basically be run maintenance-free until they get rough, which will take a long time. But it's probably not worth buying a new wheelset, in my opinion.

Water can get into hubs, and yes, it is a very bad thing, particularly if left for days or beyond. Best way for water to get in: using a pressure washer to clean your bike, or driving on the highway in the rain with the bike on a rack. Both methods are guaranteed to kill every bearing on the bike.

Sealing: both cartridge bearings or cup and cone hubs can we well or poorly sealed. The single rubber air dam in your standard cartridge bearing is wholly inadequate to protect against water and the outside world. In contrast, mid-range and above Shimano hubs with cup and cone design are very well sealed, in fact better than any of the other of dozens of different hubs that I own and ride. My old Shimano LX hubs from the mid-90's are remarkable survivors, and have outlasted innumerable epic mud-fest trips and total water immersions. Excellent seals.

Best wet-weather hubs ever: Campagnolo Record old-school road hubs with no seals but with grease ports. Get caught out in the rain? A couple of minutes with a grease injector flushes out the old waterlogged grease and they are good as new.

Grease: a vastly overthought topic, particularly for low-demand applications such as bicycles. Low stresses, low temperatures and low RPMs. I use whatever petroleum-based grease I can scoop at yard sales for $1 a tub, and will then fit to my grease injector.

You just get a grinding noise. Or do you also feel it grinding when you turn it by hand? If you only hear it, then it might be the water and grease along with some air attempting to mix together and the air giving a popping sound as it burst out of the other two unfriendly substances.

Yep... I was pretty surprised when I re-greased a UO-8 that I had been ridding in Galveston. I had occasionally ridden through deep clear water when it rained. After a year I pulled everything apart as I saw sand collections around the rim of the hubs. It looked very much like salt granules and may have been. After taking the hubs apart I was totally surprised at the amount of sand and grit just outside of the bearings. Yet I did not experience any change in sound or friction....

By the way, I use Marine Grease on everything, not that I really need it...

Well made cup and cone units with periodic maintenance do work well. I ran Campy NR hubs for years, overhauling 2 or 3 times a season motivated by rain/conditions ridden. I replaced a very few cones (I had a few bikes each year to spread the miles over), replaced the balls when they looked old, bent/broke a few axles (not the bearing design's fault) but never had a shell cup need replacing (a job I've done a few times for work).

It is that last bit that ls a basic difference. One replaces both the "cup" and the "cone" when replacing a cartridge bearing. But nearly no cup and cone hubs have replacement cups possible.

One can talk about which example of what design had this or that outcome for their riding all they want but the above difference remains as a real one and not some anecdote. Andy (who moved onto cartridge bears to not feel bad about not bothering to service them as often)

Far too much to do is made about water infiltration of hubs. It’s not nearly as bad as most people make it out to be, especially with modern (post about 1995) designs. First grease doesn’t mix well with water. It is hydrophobic and does a damn fine job of keeping water out. Seals…even on cup and cone hubs…have drastically improved from the bad old days when the “seal” was against dust and fit poorly. The rubber seals on most wheels will keep out water even if you clean with a pressure washer.

Ah, the old “my cup and cone bearings are better than those substandard cartridge bearing hubs” myth. The “single rubber air dam on your standard cartridge bearings” isn’t just a rubber air dam. These are bearings that are designed for far greater stresses and service duties than cup and cone could ever endure. The bearings used in bicycle hubs are standard bearings that are usually designed for automotive loads and automotive speeds. They last tens of thousands of miles in automobiles and will last a whole lot longer than in a light duty application like bicycles.

Additionally, you are comparing cheese to chalk. Generally a cartridge bearing is meant to be used until it doesn’t work anymore. You can do a little maintenance on them but, for the most part, they are meant to be replaced other than repaired. Replacement is relatively simple and causes no damage to the hub. Damaged cups…although rare…aren’t as easily replaced. And cones are much more susceptible to damage and more frequent replacement as well as having a greater need for periodic maintenance.

Maybe but cartridge bearings with they “single rubber air dam” seal stands up very well to water without any need for maintenance. Got several of them that have gone for tens of thousands of miles without having had to do anything to them at all.

I can agree with your sentiment but for different reasons. Not one of my bikes (13 mine and 4 my wife’s) has a loose bearing anywhere on the frames. The last tube of grease I bought was more than 4 years ago and it replaced a tube of grease from 20 years before that. I don’t use grease for anything other than threads. I figure I got 16 more years before I need another tube of grease. And I expect to be riding the same hubs, headsets, and bottom brackets when that tube runs out.

If you have serviced and inspected it and it isn't noticeable when you ride the bike I would say it is fine.
Everything wears out. Keep serviceing it and wait till it is properly worn or noticeable and then replace it. You will know when and get plenty of warning.
Hubs are simple. They last a long time.
Replacing barely worn parts for some attempt at perfection is silly.

1. Mercury T-4-C grease.

2. My former experience in industrial electric motor repair suggests a quality sealed cartridge bearing will last longer under severe conditions. Sturmey archer HBT30 for the front.

Hard to say now, the sound was only present immediatelly after the ride, not more the day after.

Next time I will check immediately.

I though it could be that the sand also gets in the axle? (I have through axle)