As a starting point, it is important to understand why you need the backpack. For most people it is a question of convenience and practicality. This is because they will be carrying a few essentials on a road trip that might not have all the creature comforts that they are used to. This guide on how to buy the best road bike backpack lists the key criteria. It then recommends a possible product.
1. Malleability, Adaptability and Portability
The backpack that you choose must easily come off the bike when you need to do so. This is particularly important during an emergency. For example it must not require additional equipment to disassemble. For this criteria we recommend the Alpkit Gourdon 25 drybag which can cost as little as $40 a piece.
2. Usable Spaces and Practicability
You need a backpack which can easily carry all the things that you need for the trip. It should also leave a little room for unexpected extras. Avoid those bags that have too many pannier hooks or even an inordinate amount of faffing. They are distracting during the trip and could cause a hazard. In this case we recommend the spacious Osprey Talon 22 which costs about $100 a piece.
3. Organization and Compartmentalization
A good quality rucksack does not require you to simply throw everything in at once. It has different compartments so that everything is organized. This helps you find stuff when you need it. Look out for a good range of hiding holes and pockets. The Deuter Bike One 20 Liter rucksack at $110 is a very good option in this case.
4. Light Weight but Strong
The last thing you need is a rucksack that adds to the already significant weight that you carry. Often these are long treks in unfriendly climatic conditions. Therefore you need a rucksack that is light on its feet. However the product must also be strong enough to hold the items you need. The Proviz Reflect 360 at $130 fits the bill perfectly on this criteria.
5. Water Resistance
You need a weather-proof product. This is because as a biker you are never quite sure how the weather is going to turn out. The best rucksacks are the ones made from seam-welded materials. If you must go for a conventional design, choose one with strong lining. Alternatively watch out for an in-built rain cover. The Timbuk2 Q at $160 is a great rucksack in this respect.
6. Padding and Comfort
The ideal rucksack should have sufficient padding to make it comfortable for the wearer. Watch out for wide shoulder rungs that do not leave bruise marks. However expect to get very sweaty since the padding will restrict air movement. Therefore rucksacks that have cooling vents are better. We recommend the Deuter Giga Pro at about $180 in this respect.
Ultimately this criteria on how to buy the best road bike backpack recommends that you set aside a budget of about $200. You can then identify the rucksack that seems to be a good compromise. It must cover your most essential selection criteria.