Water in the frame?

[Danger Dassie]

Because of the weight!!! Shees you are talking a lot of extra g here.

 

Yep, thats why a lot of models are specced with super flimsy tyres and tubes, keep the advertised spec weight down.

[Shebeen]

You obviously didn't picture the scene properly. A 220V drill with cord will restrict my style. My pre-drilling maneuvres and sparring will get me tangled in a cord.

i have watched enough 'home improvements' to know that tim the toolman taylor always asks for MORE POWER!

he also trips over power cables, but that is part of the effect. you looking for danger or convenience?

[Guest Big H]

Please do tell, if you know, tell us.

 

snip snip

 

He makes a habit of critisizing and not backing it up with meaningfull contributions. He normally follows up with snide remarks.

[LazyTrailRider]

Didn't top-end frames used to come with holes?

 

I'm pretty sure some marketing dumbass (I have an honours in marketing so am qualified to use the term) then said "but we can't have that, people will thing our frames are weak and that it's going to look crap!", after which the competition saw this and thought "hang on, these guys are clearly out to improve their aerodynamics, we should too!" and then their competition saw it and thought "crap, these guys are improving the structural integrity of their frames, we should too!" and so forth etc etc.

 

Calf paths form surprisingly quickly.

[The_Break]

Please do tell, if you know, tell us.

 

Some frame designers choose not to put a drain hole into MTB frames in the BB area because the risk of corrosion increases.

 

Most frames, especially hardtail, have other drainage points where the water is able to exit. These drainange points are sometimes purposeful and sometimes not (e.g. where production cooling water drainage holes are designed into seat and chain stays for cooling water purposes). Also if you read the warranty/customer booklet (which most LBS do not supply as required) many of the frame manufactueres who do not have drain holes specifically say youu must drain any frame water by removing the seatpost and this means they did not put drain holes in for a very specific reason.

 

Reason being, a BB drain hole is not a guarentee that all frame water will exit as even though the BB is the lowest point in the BB, there are welding beads between the seat tube and chainstays which cause high points and prevent water from exiting the chain stays andinto the BB. Also, by having BB drain holes on MTBs, more dirt and mud will get into the frame when riding through mud and water and thereby cause more blocking and corrosion due to a then higher build up of dirt over these weld beads causing less water to exit the frame. The more dirt inside your frame the higher the risk of corrosion as dirt is not corrosion neutral and adds to corrosion processes. Having cleaner water enter the top tube and work its way out via other channels or by recommended seat tube drainage is definitely something most frame manufacturers consider during their design.

 

Very little dirt will enter through the seat tube when compared to a BB drain hole for the average dirt rider.

 

So no, drain holes are not always the best option for water drainage and corrosion prevention. Each manufacturer weighs up the risks and makes there own decision as I said before and I do not think that suggesting drilling a drain hole is a good option for frames where they have been design out for a reason.

 

I think if you actually mailed a few of the R&D departments they would tell you similar reasoning for not putting BB drain holes in.

Edited January 19, 2011 by The_Break

[The_Break]

He makes a habit of critisizing and not backing it up with meaningfull contributions. He normally follows up with snide remarks.

 

Carefu! Or I may call on you to backup your criticisms and deformative comments.

[gummibear]

I have drilled both my road and Mtb frames as the amount of water we get here it will never dry on it's own and it was to much of a hassle to take post out every day.

 

I drilled them about 8 months ago and not one problem.Drilled 2 5mm holes with a battery drill and the BB out.

 

Will a frame be replaced under warrenty for water damage?

Edited January 19, 2011 by gummibear

[The Drongo]

sheesh

 

I've forgotten how this conversation started.

 

Johan, you may keep the title.

 

BIG H - what sites have you been trolling ?!?!

[Johan Bornman]

I have drilled both my road and Mtb frames as the amount of water we get here it will never dry on it's own and it was to much of a hassle to take post out every day.

 

I drilled them about 8 months ago and not one problem.Drilled 2 5mm holes with a battery drill and the BB out.

 

Will a frame be replaced under warrenty for water damage?

The answer is "most likely not". I recently had a Cervelo that was badly damaged by water, the entire alu BB shell inside the carbon frame was eaten away. The agent wouldn't replace it.

 

The damage in this case was unusual. I very seldom come across a frame that's damaged by water but very often BBs 9teh bearing part) that is damaged by water. Probably one in three BBs would have lived longer had they not been contaminated from the inside.

 

Interestingly enough, it is usually only the left side BB bearing that goes. I couldn't figure it out until the very clever Greatwhite pointed out to me that guys always lay their bikes dwn on the left size - the other side has the jockey. After races the lawns at prizegiving are littered with bikes lying on their left side. I swear I can hear the sound of water munching at those bearings and supping on that grease as we speak.

[DaLoCo]

Hmm...just had a thought. If you could drill the road at the right angle the wind could whistle through it as you ride...two different sized holes could have a nice harmonious effect

[Christie]

Carbon and aluminium has a lot of galvanic potential. Corrosion happens if the medium is right. My guess would be that the Cervelo in question got some salt water in from a rainy day at the coast, or some sweat, or energy drink with some salt in got into the BB.

Then we use aluminium and carbon fibre together in a corrosive environment at work, we use a layer of fibre glass between the two. There are hassles, though: Fibre glass is relatively heavy, has a different thermmal expansion to carbon and the layer makes the lay up unsymmetrical, and will look ugly inpainted. Perhaps then not a good solution for bikes.

[Guest Big H]

Carbon and aluminium has a lot of galvanic potential. Corrosion happens if the medium is right. My guess would be that the Cervelo in question got some salt water in from a rainy day at the coast, or some sweat, or energy drink with some salt in got into the BB.

Then we use aluminium and carbon fibre together in a corrosive environment at work, we use a layer of fibre glass between the two. There are hassles, though: Fibre glass is relatively heavy, has a different thermmal expansion to carbon and the layer makes the lay up unsymmetrical, and will look ugly inpainted. Perhaps then not a good solution for bikes.

 

I do not know much about these things but why would there be galvanic action between carbon fibre and aluminium? As I have it CF is inert? I remember in the good ole days when we still used aluminium handrails on bridges we used to bed them on epoxy and use nylon washers on the bolt fittings.

Edited January 20, 2011 by Big H

[RodTi]

China, I'm chilled. I quite like Bush Mechanic...kinda has a Boer Maak 'n Plan ring to it.

 

Drilling a BB is pretty dramatic. I give my customers a permanent markerpen and tell them to mark the lowest spot on the BB - with the bike in a normal position, obviously. I caution them that the position of the hole is in their hands and if they get it wrong....

 

Then I turn the bike upside down (BB out by now) and I tell them, as I clutch a ball-peen hammer and centre punch: "This is gonna hurt....hurt you more than me." Then I smack their prized bike with the hammer and punch. Then I make uhmmmm noises, mumbling something about, strange that it didn't crack this time, it usually does. I also comment on how remarkably little paint chipped off.

 

By now they are seriously nervous. I then take full advantage of their disposition and pull out a Makita 18V LiIon power drill and dramatically and slowly select a suitable drill bit, first picking up the 20mm bit, eyeing it and them putting it back. Next comes the woodworker's auger. I fit it in the mightly Makita and set it to run super slow. I then hold the drill, sharp side up and pull the trigger. A LED comes up and the slow-turning auger catching fresh air makes the customer shudder.

 

After that sunk in, I put it down, remove the auger and select something more suitable. Usually a 6mm. I fit this in the chuck and wildly pull the trigger a couple of times like a laaitie revving a City Golf. I try and look gleeful and psychotic.

 

I then take aim at the BB. I widen my stance, warning bystanders that hot alu shavings will be flying around, looking for shoes to drop into. Once they are at a safe distance, I fire up the Makita, aim and drill.

 

I then put the drill and accessories away and inspect my handywork. I feel inside, outside, blow away the swarf and make hmmmm noises, before fitting the BB. If anyone leans closer, I warn them of the unbearable heat generated there and tell them not to touch.

 

I wait for things to cool down and then inspect it all.

 

I use the period of relief to discuss filed out cable stops. I punctuate this discussion by showing them a series of tungsten carbide burrs and my high-speed dremel that sounds like a dentist's drill. I vaguely mutter about the risks of the dremel ripping the stop right out of the frame, leaving a sharp, gaping hole.

 

Is that "moerit" enough? Anyone for a BB conversion?

 

 

You had me smiling ear to ear on this one JB - possibly since having met you once, I could actually picture you doing this, down to the "laaitie revving the Citi Golf"...

[RodTi]

Anyhooos - back to the original question - in answer to a Hubber long since past caring what the outcome of this might be...

 

 

Despite all the disagreements so far - can we agree on this one thing:

 

[Tongue inserted firmly into cheek]This dude, had it wrong from the get-go, and then gave up trying...

[Christie]

As I have it CF is inert? I remember in the good ole days when we still used aluminium handrails on bridges we used to bed them on epoxy and use nylon washers on the bolt fittings.

 

Oom H, the epoxy is not the problem, it is the carbon. If it is 100% enclosed in epoxy, it would not corrode. On bicycle frames and most things that try achieve low mass, designers/manufacturers try use as little epoxy as possible, so the carbon gets exposed easily, especially on the inside of the frame. On the ouside. they usually add an extra clear coat of epoxy and or paint to cover any exposed carbon.

 

here is a galvanic chart. (graphite = carbon)

http://www.corrosionist.com/Corros1.gif

[Guest Big H]

Oom H, the epoxy is not the problem, it is the carbon. If it is 100% enclosed in epoxy, it would not corrode. On bicycle frames and most things that try achieve low mass, designers/manufacturers try use as little epoxy as possible, so the carbon gets exposed easily, especially on the inside of the frame. On the ouside. they usually add an extra clear coat of epoxy and or paint to cover any exposed carbon.

 

here is a galvanic chart. (graphite = carbon)

http://www.corrosionist.com/Corros1.gif

 

OK I suspected that carbon was the foe here. Thanx, learnt something new.

 

Also touched an oddity...... In cycling it is called carbon, in fishong rods it is called graphite

Edited January 21, 2011 by Big H