drain holes in BB shells

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mig
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drain holes in BB shells

Postby mig » 2 Feb 2017, 11:59am

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
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Re: drain holes in BB shells

Postby Brucey » 2 Feb 2017, 12:04pm

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

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

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Gattonero
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Re: drain holes in BB shells

Postby Gattonero » 2 Feb 2017, 1:52pm

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

Image

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.
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...

Threevok
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Re: drain holes in BB shells

Postby Threevok » 2 Feb 2017, 3:19pm

Gattonero wrote: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
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Re: drain holes in BB shells

Postby Mr Evil » 2 Feb 2017, 5:14pm

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.

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Mick F
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Re: drain holes in BB shells

Postby Mick F » 2 Feb 2017, 7:48pm

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

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Gattonero
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Re: drain holes in BB shells

Postby Gattonero » 2 Feb 2017, 9:19pm

Mr Evil wrote: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
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...

Al Wright
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Location: Dublin

Re: drain holes in BB shells

Postby Al Wright » 2 Feb 2017, 9:43pm

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"

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Gattonero
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Re: drain holes in BB shells

Postby Gattonero » 2 Feb 2017, 9:53pm

:mrgreen:

yet, you can poke the drain hole clean with a small allen key or a spoke :wink:
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...

landsurfer
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Re: drain holes in BB shells

Postby landsurfer » 2 Feb 2017, 10:08pm

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 !! ... :)
Be More Mike.
The Road Goes On Forever

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Mick F
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Re: drain holes in BB shells

Postby Mick F » 2 Feb 2017, 10:54pm

I repeat.
Mick F wrote:No drain in mine, and no condensation, and no rust.
1986 531c
Mick F. Cornwall

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Gattonero
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Re: drain holes in BB shells

Postby Gattonero » 3 Feb 2017, 12:14am

Mick F wrote:I repeat.
Mick F wrote: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? :roll:

Image
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...

francovendee
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Re: drain holes in BB shells

Postby francovendee » 3 Feb 2017, 8:25am

Gattonero wrote:
Mick F wrote:I repeat.
Mick F wrote: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? :roll:

Image


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

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Gattonero
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Re: drain holes in BB shells

Postby Gattonero » 3 Feb 2017, 8:44am

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
It is by riding a bicycle that you learn the contours of a country best,
since you have to sweat up the hills and coast down them.
Thus you remember them as they actually are...

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Mick F
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Re: drain holes in BB shells

Postby Mick F » 3 Feb 2017, 10:40am

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?
Mick F. Cornwall