^^^ This. ^^^
Look at their stuff here:
ORTLIEB - Produkte / Products /Produits
The bags are tough, durable, and completely waterproof. They're designed to mount on the bike quickly, easily, and securely. And you can take them off just as quickly. They're pricey, but you certainly do get what you pay for with them. I expect mine will make it through to my retirement in 12 years.
I prefer the older QL2 mounting system to the QL3. Near as I can tell, part of the QL3 system mounts to the bike. I need the flexibility of using other bags, and switching my bags from bike to bike., so it's QL2 for me.
The answer is: use a Kitter!
Look at their stuff here:
Bike Buckets: an inexpensive pannier system you can make
The kittiers are tough, durable, and completely waterproof. They're designed to mount on the bike quickly, easily, and securely. And you can take them off just as quickly. They're almost free, so you certainly do get way more than what you pay for with them. I expect mine will make it through to my retirement in 20 years.
Here's some pics of mine, one on the bike, and one in the dark showing the super-reflective accents I have added to assist drivers who don't know where they should be driving.
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