Bicycle Mechanics - We rode through deep water. Will we now have bottom bracket issues?

Is there any damage that this will cause, like water getting into it? Anything I should do to fix or prevent rust?

I have a LHT which Surly says is a "Shimano, UN53. 68x118mm".

My son was on a Trek 520, but they don't specify theirs.

I believe that both of these bikes have sealed BB's. If that is the case there should be no problem with water into the BB's. In the frame there may be some moisture remaining as it is hard to get it all to drain. I would remove the BB's and dry the inside of the frame. Then spray some Triflow in the area to displace any remaining moisture.

If your frame has a drain hole on the BB shell, there should be no issue, as any water which has entered, should be able to drain out. Also, these BB's have been used for MTBing for years, and ahve survived getting wet and muddy, getting it wet once should not matter.

I believe that both of these bikes have sealed BB's.

Sealed BB's does not mean it is impervious to water and dirt contamination.

Sealed BB's does not mean it is impervious to water and dirt contamination.

But sealing them does make water and dirt infiltration much, much, much more difficult. And, in the case of Shimano bottom brackets, nearly unserviceable. Ride 'em until they stop working, scroca, then replace. Immersing the bottom bracket is a fairly common occurrence in mountain biking as jimc101 has pointed out. It's not anything to lose sleep over.

But sealing them does make water and dirt infiltration much, much, much more difficult.

High quality sealing. There are plenty of 'sealed' anything out there that are no more waterproof than a piece of blank paper.

Sealed BB's does not mean it is impervious to water and dirt contamination.
True but it means if the bottom bracket's seals are compromised, there is nothing you can do the fix it. I'd just continue to ride it until the bb made it obvious it had been damaged.

As jimc101 noted these thing have been used on MTB's in dreadful conditions for years and usually survive for very respectable times.

I believe that both of these bikes have sealed BB's. If that is the case there should be no problem with water into the BB's.

This is a popular misconception. The sealed bearings used on bikes are designed to seal against dust and a light spraying of water, but are not adequate to seal against positive hydraulic pressure such as when parts are submerged.

The irony is that classic open bearings often do better against serious water exposure. They don't keep it out, but the grease will protect the bearings for a time, and being open the inside will dry much faster than with a sealed bearing.

The sad reality is that sealed bearings often do a much better job keeping water in, than out.

The most important thing to do after submersion is to dry the bike as quickly as possible, and not let allow the bearings to stay wet for days and weeks.

I have lot's of experience with wet riding including a few floods, the deepest being over the top of my wheels. simply put the bike in a warm place (the best is inside a car parked in the sun), and give it enough time to dry. I've never torn down or re-lubed bearings or chains after rain or floods, and have never had a rust or bearing failure problem.

I've never torn down or re-lubed bearings or chains after rain or floods, and have never had a rust or bearing failure problem.

Yeah but that's because you take care of your bikes.

Yeah but that's because you take care of your bikes.

Yes, but I spend vastly less time on bike maintenance than most of the active riders on this forum. Bearings are greased via grease fittings (or if not, field-stripped and serviced) every 5,000 miles or so, chain lubed every 1,000, and washing happens only while riding in the rain.

Brake shoes and all cables are replaced as needed, or after 2 years. Tires when cut or worn (they don't last long enough to dry out).

My total bike care effort can be measured in minutes per 1,000 miles, and my last mechanical failure on the road was a broken RD wire 5 years ago (I knew it was going, but put off replacing it too long).

Thanks for the feedback everyone. I will probably follow the school of thought that says to ride until there is an obvious problem. There's nothing wrong right now that I can tell.

High quality sealing. There are plenty of 'sealed' anything out there that are no more waterproof than a piece of blank paper.

The kind of bottom bracket that scroca is using is a cartridge bottom bracket that is of a high quality sealing and is sealed well enough to withstand immersion for short periods...on the order of hours. It's not sealed like Shimano hubs are sealed. It's sealed more like a Phil Wood hub (and bottom bracket) is sealed.

This is a popular misconception. The sealed bearings used on bikes are designed to seal against dust and a light spraying of water, but are not adequate to seal against positive hydraulic pressure such as when parts are submerged.


If scroca were riding at a depth of 10s of feet, your point would be valid. However at a depth of a few inches to a few feet, the hydrostatic pressure is only minimally higher than atmosphere. At 1 m, for example, the pressure is only increased to 16 psi. At the fraction of a meter depth that a bike might experience, the change in pressure is almost too small to measure.

....not adequate to seal against positive hydraulic pressure such as when parts are submerged....

Positive pressure would be a high pressure hose, not 1ft below the surface. Momentary submersion has never been an issue for any of my open and sealed bearings.

Well, I took the bikes to the lbs to let them have a look. Turns out the Surly held up just fine.

The Trek had a weep hole that evidently let in water, that consequently got into the bottom bracket. So we are going to replace that one.

Next time I guess we walk through the water carrying out bikes.

The kind of bottom bracket that scroca is using is a cartridge bottom bracket that is of a high quality sealing and is sealed well enough to withstand immersion for short periods...on the order of hours. It's not sealed like Shimano hubs are sealed. It's sealed more like a Phil Wood hub (and bottom bracket) is sealed.
Phil bearings are no better than anyone elses at keeping out water. They are dust seals and nothing more. It takes labrinth seals to keep water out and grease in.

I had an Easton EA-90 SLX sealed ceramic wheel bearing fail a day or two after a ride in a real downpour. I am convinced the failure was caused by water infiltration.

During warranty discussions with Easton's rep, he admitted that an unsealed bearing was probably better against water damage because the seals keep the water inside if it happens to find its way in there. For that to work, the open bearing must be serviced much more frequently to make sure the bearing always has adequate grease.

Easton sent me the replacement parts and a tube of their grease by two day delivery after just a phone conversation, great guys.

Some pretty unrealistic expectations for a $20 BB cartridge I`m afraid. A better explaination of `sealed` in this case would be ` not servicable`.

I`m sure that some mtb riders abuse their BB and tell about it but I doubt they `get away with it`. Replacing Shimano UN 53/54 cartridges is a pretty common occurance in all the shops I`ve worked in and the reason is always the same - water infiltration.

Most common on the crank side. Personally I`d suggest a teardown just to dry out the water thats probably still inside the frame. It can`t get out on its own. But thats another thing professional riders do too - tear down their bikes a lot.

Phil bearings are no better than anyone elses at keeping out water. They are dust seals and nothing more. It takes labrinth seals to keep water out and grease in.

From the Phil Wood website (http://www.philwood.com/products/bearingpgs/stand.php)


Any of our bearings with an “x” in the part number have seals that are as good or better than those found in the highest quality submersible motor and pump bearings.



The bearings 'marked with an x' are these.


PWX05 6805 25mm 37mm 7mm Shimano, Raceface, FSA, SRAM, Truativ OBB, 2nd Gen 20mm Thru
PWX06 6806 30mm 42mm 7mm BB30
PWX07 6807 35mm 47mm 7mm White Industries Freewheel 16 Tooth
PWX08 6808 40mm 52mm 7mm White Industries Freewheel 17+ Tooth
PW900 6900 10mm 22mm 6mm FSA
PWX01 6901 12mm 24mm 6mm Front Racing Wheelchair & BMX Mini Hubs
PWX02 6902 15mm 28mm 7mm Phil Wood Cassette and Rear Hubs
PWX03 6903 17mm 30mm 7mm Phil Wood Square Taper Bottom Bracket
PWXR8

I'd say that if the bearings match those found in submersible motors and pumps, they are pretty much water proof and not just sealed against dust.

On the other hand, even dust seals like those used by Shimano on their hubs should do an adequate job...along with the grease in the bearings... of resisting infiltration from a short, shallow immersion.

I'd only have replace the bottom bracket if there were clear evidence of impending bearing failure...grinding, lack of smoothness, etc. That's what you are supposed to do anyway. Just because the bike gets wet isn't a reason to panic. Bikes can endure a lot more abuse than people think:rolleyes:

Some pretty unrealistic expectations for a $20 BB cartridge I`m afraid. A better explaination of `sealed` in this case would be ` not servicable`.

I`m sure that some mtb riders abuse their BB and tell about it but I doubt they `get away with it`. Replacing Shimano UN 53/54 cartridges is a pretty common occurance in all the shops I`ve worked in and the reason is always the same - water infiltration.

Most common on the crank side. Personally I`d suggest a teardown just to dry out the water thats probably still inside the frame. It can`t get out on its own. But thats another thing professional riders do too - tear down their bikes a lot.

And there is no need to replace a bottom bracket that is meant to be used until failure unless it has failed. Mountain bike riders 'get away with it' because they use the equipment as it is meant to be used...until failure. They then replace it. From my experience, the 'failure' part of the equation is a very long time in coming. I've never replaced a Shimano cartridge bottom bracket, nor any other brand, because it has failed. I've replaced lots of them to upgrade but never because of actual failure. The old ones either gather dust in my garage or get recycled into project bikes.