I'm looking for a square taper (JIS) bottom bracket for all weather commuting. I ride in lots of wet and grungy conditions, and I'm currently replacing the bearings in my Phil Wood bottom bracket every 18 months to two years, which is a drag. Does anyone have any recommendations for a BB that is well sealed against water and grime?

Thanks.

Z.

have you noted Phil's mud shield pieces you fit over the spindle
after tightening the mounting rings, add some more O rings
around the spindle, between the arm and the seal ring..
to seal even better around the shaft.

https://www.philwood.com/products/bbp...dcupguards.php


you could Bid on a WTB Grease Guard BB , they are not made anymore,
so that may have to be your source.

but a needle grease gun tip, will push fresh grease in and purge
out the old grease..

another discontinued one, SKF-Sachs, the bearing cartridge
with sealed bearings
was behind shaft packing in the cups, further shielding the bearing cartridge..

If you can find one, https://janheine.wordpress.com/2011/01/27/skf-bottom-brackets-world-exclusive/ would be my recommendation. I've got one on my commuter, bought used.
Don't know what it had been through before but I've put it through 60-100 miles/week each year, incl salted/sanded winter roads for the last 3-4 years.
It just keeps on turning, smoothly as ever.
Chains, cassettes, pedals, derailers, cranksets comes and goes, but this puppy simply shrugs it all off.

Thanks for the reply. I spoke to someone at PW about the mud shield, and she told me that they were more for mud than water. But I ordered a set anyway, they can't hurt.

I have an SFK, but it's the wrong spindle length. Good BB, but hard to find.

I think the bigger worry about a BB is that the cups will seize in place in the frame. Pretty much the only way to avoid this is to remove them every sometimes and regrease what you put back in.

Because of this, my strategy for a high-use, bad weather BB is something mid-level. Good enough to hold up, but no so good that it does not compel me to pull it every now and again.

jim

I often rode trails paved with crushed limestone even when they were wet. The powder was very sticky and abrasive. Ordinary cartridge BBs did well for me.

I think you may need to repack more often. The grease itself acts as a seal until it circulates enough to let the grit get to the bearings. Just use a thick grade of boat trailer grease.

Don't be fooled into believing thatmost sealed BBs are actually sealed. The sealed cartridge bearings used on most are made for things like electric motors, and the seals are dust seals, not weather seals (you don't run electric motors out in the weather). If you want a good all weather bearing, you want good baffles, with a gap between the exterior and bearing ears so water cannot wick across it, and most important you need a way to regrease.

I use an old SunTour Grease Gaurd BB, which is fairly weather resistant, but most important allows through the spindle grease injection, so I can replenish the grease, pushing out contaminated grease easily and often without disassembly.

As an alternate to a pricey serviceable BB, you might go the other route, buying the least expensive BB and considering it a sacrificial lamb, expecting to replace it more often, but it could still cost less in the long run.

I'll second the recommendation for using an ordinary BB cartridge. A run of the mill Shimano lasted 10k miles through Minnesota's snowy, salty, and sandy winters. The second one has 8k on it so far. Not too bad for a few bucks and no maintenance. The rest of the drivetrain however.... :-/

Maybe the statement on specifications, stating the seal Phil wanted for those bearings
was submersible pump .. and having it true went off to the Farm
Mr Wood bought when he retired and sold his machine shop ,
to the current owners, who obviously, kept his name on the business..

What is your service situation? stream fording,, ?

get 2 years only, out of those? might go thru the typical UN 'XX' in a winter, then.
but they are cheap, and fast, to replace ..


The mud shield, which I have yet to hold one in my hand,
would not have much seal against the mounting ring splines
Just an O rings on the high spot tips of the spline..
Maybe a bit of bathtub caulk to better seal there, ,
+ the o rings around the spindle pressing around the
edge of the hole..
may shield off ahead of the cartridge..

since Phil BB mounts entirely inside the BB shell ,
the mud rings would come out far enough,
to cover the BB shell face, [presumption]
so maybe that contact is good enough..

***

I had ideas about the leather packing and pump cups,
that were the main product of the company
that took on the making the Selle Anatomica saddles,
In the last few years... about shaft packing around the BB axles

Shaft packing is what goes around the propeller shaft
to keep the Ocean out of the Engine room..

those mud shield things may be useful in that direction.
further O ringed.

Used to be a Zirk kit for loose ball BB's,
it was a thick sleeve between the cups
that you pumped grease in around the axle,
till it came out past the bearings.. with a zirk fitting
for mechanic's grease guns

Awesome advice. Shimano makes really good sealed BBs for this. Greasing threads does help, but having an option that doesn't break the bank is valuable.

I have found that, unless I strictly ride (relatively) clean asphault, non-sealed BBs just attract grit. It's the nature of the system...easily serviced but that also means you'll eventually have to service it.

That's if it has cartridge bearings. Many Shimano BBs are sealed and seem to last. They are purpose-made, not built with electric motor bearings.

Yes, right. I accidentally dropped "cartridge" from the phrase sealed cartridge bearings in the second sentence. I've fixed it now.

I got just a year out of mine, 1 winter.

I made seals out of regular squishy foam. Cut a doughnut shape and fit it over the axle between the cup & crank arm. Works really well.