Pannier Precipitation Problems Part 1 (Drilling holes)

Every time I go overlanding I have had to deal with Panniers full of water and I finally figured out a way to deal with it. I should point out that when I rode Harley Davidsons I never had this problem, because I never took them off road; so this article is dedicated to people whose bikes strike trees and rocks or fall over from time to time.

In the beginning the panniers were perfect, no scratch’s, no dents, they were water tight and life was good. However falling down Mosquito Pass (CO) , falling up Bethel Ridge (WA), and sliding in the mud a Sturgis (SD) did a number on them. I had foolishly thought the panniers would keep their waterproof integrity while doing off road riding, only to learn during the return trip in a deluge that they do not. My Advise: dont even worry about the rubber O-Ring in the top of your pannier and make plans for it to fail.

The end result is my panniers fill with water during long rides if it rains. You may think “Dude BMW makes waterproof bag liners” and to that, I will tell you that “they do not make good ones” and please check out part 2 of this article about Bag Liners

Rock it with a step drill

lets start with the assumption that water might get in, and the best thing to do is to allow it to drain out rather then build up. Step one is to figure out where the water ‘pools up’ when your riding and mark that as the place you want the hole. The nice thing about the step bit is it allows you to “Work up” to the hole size you want so you can check your plugs and make sure they fit.

Where does the water set?

Someone might ask where does the water go in a pannier when your riding around? We know that water seeks its own level and takes the path of least resistance. I was 90% sure where I would need to drill the hole, but I have action cameras to and used them to apply the scientific method to test my hypothesis. Funny note you will need to put black flakes of something in the water to help you see whats going on because water in a silver container at motion is almost invisible. P.S. yes water goes to the inside back of the pannier.

Check your plugs for fit

I used a 1/2″ hole for a 1/2″ Rubber Plug. You will see these things listed as

  • Flush Plug
  • Grommet Hole
  • Panel Plug
Pannier bottoms with plugs

You can see the plug does not get in the way and is easy to remove when your putting on your rain gear, or even at the end of the day. Anyone who has used a cup to try to get water out of their panniers gets what I am saying here.

But WAIT what about River crossings!!!!! Are you crazyWhat about that!!!! I imagine hearing outrage that I may not have considered intentionally going into waters and what might happen? If your thinking that and getting ready to have a stroke right now, please take a deep breath – I’m getting to that.

The plug is actually rather water tight

So as long as your drill the right hole size for the right plug size it will be a significant fit. I filled the panniers with water and let them set for a while with no leaks. The way low pressure and high pressure systems work is that during a water crossing the pressure of the water will actually make this seal tighter. But these plugs are cheap and light so I keep a few extra (lightly oiled) in a small bag just incase I need to change them out at any time.

Whats the inside look like

If your curios about the inside, its simple and pretty low impact. I only show you this picture as a reference. If you choose to remove the plug you would do that from the outside without having to remove all your gear from the pannier.

Cheap shammy

I have mentioned this before and I will mention it again, a very cheap shammy from the the car wash is great to keep at the very bottom of the pannier.

  • If anything leaks let it get caught by something super cheap at the bottom of the stack
  • When loading in the morning its nice to wipe the dew off your seat with the shammy
  • If its only a light rain and you dont remove the plug the shammy will grab a lot of the water

Please check out Part 2 of this about “Bag liners