Singlespeed & Fixed Gear - Bottom Bracket Drain

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View Full Version : Bottom Bracket Drain


subsistbmx@hotm
05-17-07, 11:34 PM
Is a hole on the bottom bracket needed ? I just got a SPICER several days ago and it doesn't have one, anyone think I should drill out a whole or cut it into a shape of Illinois (hah, kidding) ? I guess I'm just not sold on it's use..


Fugazi Dave
05-17-07, 11:37 PM
Sort of depends on if you wind up with water in your frame. I've never had that problem, so I'm content with my hole-free BB shell. Just put some grease on the seatpost and you're probably fine.

subsistbmx@hotm
05-17-07, 11:39 PM
Sorry, I don't get your grease on the seatpost comment. Rust in my seat-tube ?


mander
05-18-07, 12:00 AM
No, the grease is to seal it off. The seat tube is where most of the water gets in. Just drill a hole, 3/16" is a good size. It only takes a minute and it can only benefit your frame.

Landgolier
05-18-07, 12:42 AM
In Chicago, hells yes. Even if you never ride in the rain, temperature differentials will result in condensation in the frame. If you head out in the rain, and you remember, put a square of tape over it, and take it off when you get back home.

mander
05-18-07, 01:26 AM
^ I never tape my drain hole. Any water than gets in will get right back out again. It's self-draining. That's science.

Landgolier
05-18-07, 01:56 AM
^ I never tape my drain hole. Any water than gets in will get right back out again. It's self-draining. That's science.

Yeah, but any particles of road grit that get up in there and become one with your BB grease aren't going anywhere. That's also science.

Retem
05-18-07, 02:02 AM
dude use some frame saver and get onwtih life I have never had a frame with a bb vent so....

Momentum
05-18-07, 02:26 AM
Drill a hole - it takes five minutes, causes no problems and could save your frame from rusting.

I read somewhere (probably Sheldon's site) that you can put in a piece of straightened spoke with the head inside the BB shell. It keeps the hole sealed from grit but can bounce around a bit so that water gets out and you can oush it in to drain it.

Sounds like hassle to me, so mine just have holes in them.

mander
05-18-07, 10:16 AM
Yeah, but any particles of road grit that get up in there and become one with your BB grease aren't going anywhere. That's also science.

What harm does the grit do?

Also, last time i replaced the bb on my alu tourer, I found a crapload of sand in the undrilled bb shell.

the pope
05-18-07, 10:24 AM
holy crap here we go drill the hole then the tape then the whatev down the shoot hole with the grit and the condesation that's a new one its a wonder we keep these on the road

bottom-bracket
05-18-07, 12:10 PM
You bike will be much safer if you just don't ride it..

Surferbruce
05-18-07, 12:33 PM
drill it.

wallah
06-18-07, 12:23 AM
I just did 2 coats of framesaver in my frame tonight....I'm sure I'll sleep better, but do we really have enough rust in our metal frames over the years to weaken the tubing?? That is the question.

LóFarkas
06-18-07, 02:06 AM
What harm does the grit do?

Also, last time i replaced the bb on my alu tourer, I found a crapload of sand in the undrilled bb shell.
If it gets into BB bearings it kills them in no time.

squeakywheel
06-18-07, 06:03 AM
Put the drill down and go ride your bike.

BTW, I think the grease on the seatpost is to prevent it from seizing.

travsi
06-18-07, 06:13 AM
i also thought that in theory, a well greased seatpost would keep
any water from getting in there (not including condesation). but
after a week of rain, my undrilled bb shell let me know it was full
of water, because when i leaned my bike against the wall, the angle
was just enough to let the brown soup run out of the hole for the
axle; meaning that the bearings were bathed in a pool of water, mmmm...

Hocam
06-18-07, 06:19 AM
There are other ways for water to get into your frame, besides your seatpost.

Got a headset on there, aka is your bike not a unicycle? Water.
Water bottle braze ons? Water.
Tiny little holes in the chain and seat stays near the collar and bottom bracket? Surlys have this. Water

Know what water does to bare cro-moly steel when it can't go anywhere? Rusts.

Use frame saver and drill a small hole, you'll be fine. If you're worried about grit in your bottom bracket, more of it's comming in through the spindle anyway. Also, stop being an njs hipster and buy a catridge BB for 15 or 20 dollars and then you can't get your panties in a bunch over it.