If I get stuck out in the rain I'll flip my bike over to direct the water towards the drain holes on the other places of my bike or through my seat tube since there aren't really any bearings up there to worry about. It works well enough and a lot less hassle then drilling out a new hole. It is surprising how much water a frame can hold though.

 

It works well enough and a lot less hassle then drilling out a new hole.

Well, I'd dispute that. It might be a little less hassle - once - but you have to do it every time you ride in the rain. Drilling a hole is not a big hassle - it's a couple minutes to get set up, a few seconds with the drill - and then it's done.

I'd do it. Sheldon recommends it unequivocally in his article on frame refinishing and dealing with rust.

If the frame doesn't have a drain hole under the bottom bracket, drill one. This will help to prevent internal rust in the future. The down tube, seat tube and chainstays all should communicate with the bottom-bracket shell, so they drain through this drain hole. There should preferably be no pockets where water can collect.

 

My Ridley is carbon of course. I kind of see drilling a hole as they have already drilled one for the BB cable guide, so it must be ok. Still - taking a drill to a $1300 frame is onerous.

 

If the cable guide is held on with a screw, and the hole goes all the way through, you could just use the existing hole. Remove the screw after a rainy ride and let it drip for a few hours before putting it back.

 

You could pull the cable guide bolt every time, but honestly the best solution is just to drill a hole. Your Ridley is carbon but I bet the BB shell is alloy unless it is a new-generation with the PF30 BB, I believe those are a full carbon BB shell. Having a hole to drain water means no water will build up in the shell when you are riding and your bearings won't be turning through a puddle.

 

@ Eric
The Excalibur uses 2 Al English-threaded inserts on either side of the carbon BB, so the shell is actually carbon. The cable guide screw is drilled in the carbon and they put an alloy threaded sleeve inside the BB to retain the screw, so...

@ JCav Nice idea, simple enough. However, because of that screw sleeve it wouldn't be possible to drain all of the water out, unless maybe you shook the bejeezus out of the bike for awhile. So it really needs a 2nd hole.

 

Or even better is to remove the screw holding the cable guide and replace with a pop rivet, which is hollow. Then the water drains right out.

 

Pop rivets are not hollow.

 

Not sure which ones you're using, but I've been using them for over thirty years and I assure you that they are, indeed, quite hollow. I don't know what kind is in that pic you posted, but the center pin is easily driven from the usual pop rivet once installed.

 

The body of the rivet is hollow, but the mandrel breaks off and remains inside. Yes you can knock out the mandrel. But you reduce the pull out strength. And you're only left with a 1/8" hole.
Also, if in CF, you'd want to use a washer inside the BB. Having a washer and secondary head inside the BB will allow ~1/8" of water to remain in the BB.

 

The only worry you have is not doing a clean drill job. Start with a small bit and drill a pilot hole. Then use a larger bit with light pressure so that you don't shred the CF but rather cut it with the bit. Clean up the edges of the hole both inside and out with sandpaper and if you want to you can dab a little nail polish, model paint, or auto touchup paint around the hole. It will do NO structural damage to the frame.

 

I have a Ridley Excal and it does pull in a ton of water when it rains. The water on mine tends to enter through the slit in the seat tube where the seatpost fits. Cover this slit up with tape and you will prevent 99.9% of water from getting into the frame in the first place. I used some of the heavy/clear chainstay protector tape to cover it up and have checked the bb multiple times after getting stuck in the rain and have never had an issue.

For draining (if you must, or just to put your mind at ease), simply pull the seatpost and turn the bike upside down. It takes less than a minute. No drilling required.

 

an issue. For draining (if you must, or just to put your mind at ease), simply pull the seatpost and turn the bike upside down. It takes less than a minute. No drilling required.

And - assuming that the chainstays and downtube are open to the BB, some of the water runs down those tubes! Drill a fliipin' hole (and use my dribble valve idea that I've used for decades) and never have to think of, or deal with, BB water ever again -

http://forums.roadbikereview.com/bikes-frames-forks/bb-drain-hole-315013.html

 

Nope, as I said in one of my replies, it is indeed a carbon shell with an Al insert on either side (threaded for English), so the center of the shell is carbon, which is why they used an Al screw sleeve, so the cable guide attachment screw has something to bite into.

 

Yes, Sheldon Brown recommends drilling a drain hole in metal bottom brackets. My question is this: Manufacturers spend tremendous amounts of thought, labor, money and testing to make their bike better than their competitors in every way. Why then, isn't that crucial BB drain hole made at the factory?

I'm thinking there might be a reason . . . .

 

then, isn't that crucial BB drain hole made at the factory?

I'm thinking there might be a reason . . . .

The reason is the same one why the vast majority of bikes sold don't have a drain hole. It costs extra money to do it and hardly any customers will ever notice. It has nothing to do with compromising the strength or durability of the frame. Nothing.

 

Hmmm...It doesn't rain as much in China? Dunno...