drain holes in BB shells

[mig]

yay or nay?

i have one in a 631 steel race frame that only ever pokes its nose out during the two or so dry days that the summer offers each year. are they recommended for winter conditions?

[Brucey]

'tis better if you can stop water from getting in to begin with, but they usually do more good than harm

cheers

[Gattonero]

If you are worried about the frame, there is a spray from Tectane that works very well against rust and corrosion



Having used this extensively on Dutch style bikes (after being suggested by the Azor manufacturers), it's well worth.

But since you don't use the bike extensively in wet conditions, you shouldn't have a big problem with the frame "as it is".

Even tho, nothing wrong in drilling a 4mm hole in the middle and lowest point of the BB shell. No structural problem whatsoever, even less because of being a round hole.
And most important, let the bike dry in a heated place, if possible.

[Threevok]

If you are worried about the frame, there is a spray from Tectane that works very well against rust and corrosion

Oooh - noted - thanks

I've had some concerns lately about my Single Speed and that looks the ticket.

[Mr Evil]

Definitely. Even if you could completely seal every hole in the frame, you can still get some water inside from condensation when you take the bike from somewhere warm to somewhere cold.

[Mick F]

No drain in mine, and no condensation, and no rust.
1986 531c

[Gattonero]

Definitely. Even if you could completely seal every hole in the frame, you can still get some water inside from condensation when you take the bike from somewhere warm to somewhere cold.

You cannot take the chance, as you won't remove the BB every month or so.
Given that a drain hole creates no harm, is better safe (having one) than sorry.
You can always thread it M4 or even M5, and put a short screw

[Al Wright]

Murphy's Law when applied to drain holes generally predicts that;
"the smallest hole shall eventually empty the largest container unless it is designed as a drain hole, in which case it shall clog"

[Gattonero]

yet, you can poke the drain hole clean with a small allen key or a spoke

[landsurfer]

Get a .5mm / 1/32 split pin .. insert legs into drain hole ... open , leaving at least 10mm outside the BB, water will not collect inside the BB as the motion of the split pin will prevent meniscus effect... and it will drain clear .....
"My Professional opinion" ... put some tape over it or fill it with epoxy !! ...

[Mick F]

I repeat.

No drain in mine, and no condensation, and no rust.
1986 531c

[Gattonero]

I repeat.

No drain in mine, and no condensation, and no rust.
1986 531c

Yes, yours.
Most people are not that lucky, and since the damage can be irreversible and the prevention so easy, why taking the chance?

[francovendee]

I repeat.

No drain in mine, and no condensation, and no rust.
1986 531c

Yes, yours.
Most people are not that lucky, and since the damage can be irreversible and the prevention so easy, why taking the chance?

Wow! That looks nasty, did it wreck the threads in the frame in getting it out?

[Gattonero]

The BB shell was fine, the BB unit was thrashed anyway.
You can see the little pool there, a drain hole would have not saved the BB unit in the long-term, but reduced the amount of water there, thus giving some help and arguably improved the lifespan of the BB unit itself

[Mick F]

In all the years of riding and maintaining bikes, I have never had an issue like that.
Not just my 1986 Mercian.

Where does the water get in from?