After a couple days of research and not finding anything I have decided to make this thread.
The problem is with the pedal thread holes on wide cranks. I noticed that on my DX cranks the threaded hole for the pedals goes all the way through out the other side. My pedals when screwed in all the way only extend halfway through the hole. I am worried about water and stuff getting into the other end of the hole, rusting and breaking down the metal, and causing weakness. What do people do about this, or am I just paranoid?
Really woudn’t worry about it, structural rust damage in thick materal like a crank is very unlikely. If you’re really bothered pack some grease in the hole, oir find a plastic plug as used in the KH '03 cranks.
This isn’t anything to worry about. Most cranks are made of a metal that is resistant to corrosion so you’d have to leave your uni out in the rain to experience any significant damage… I’ve been doing no more than hanging my uni in the garage after my rides (muddy, rainy or not) and it’s been doing fine for years.
The only thing you should be doing is putting a little anti-sieze on your pedal threads before screwing them into the cranks. This will ensure your pedals don’t rust themselves into place, if they do decide to rust. Be sure to put a fresh coat of anti-sieze on your pedals (and splines) at least once a year, if not twice.
Remember a seal works both ways. You may think you’re only keeping moisture out, but at the same time, you’re also keeping moisture in… that is… any moisture that works its way into the crank will stay there longer with a cork than without.
I’d say its best to leave it open and let it air dry after your rides.