Originally Posted by
mander
In this sport we all have our own values but getting more aero makes sense for a randonneur IMO.
Znomit do you think the pika is a bit big? It looked to me like a good sized bag for especially long rides, but maybe overkill for shorter stuff and rides where you won't need much extra clothes? How is the compaction on it if you aren't stuffing it completely full?
I'd say it's pretty good. It won't be a small bag. My opinion is that you want to reserve "completely full" less-common situations. It would be bit "over kill" if you don't need a medium-to-large pack. It looks like you can roll it down smaller than 6 liters.
The Carradice and, (as far as I can tell), the Ortlieb, are always the size they are.
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* The old-style Carradice saddle bags run from 9, 15, 18, 24 (!!) liters.
http://www.carradice.co.uk/index.php...&product_id=56
* The SQR Carradice saddle bags are 16 liters.
http://www.carradice.co.uk/index.php?page_id=category&category_id=13
* The Relevate Pika is 6-12 liters. The Viscacha is 6-14 liters.
https://www.revelatedesigns.com/inde...=4&ProductID=1
* This Ortlieb seatbag (S and M) is 1.5 and 4 liters.
http://www.ortlieb.com/_pdf_en/seatpostbag.pdf
* This Ortlieb saddle bag (S, M, L) is 0.8, 1.3, 2.7 liters.
http://www.ortlieb.com/_pdf_en/saddlebag.pdf
* The Topeak bag (mentioned above) is 1.7 liters but you could stuff more things in the water bottle pocket. It requires a lot of exposed seat post.
http://topeak.com/products/bags/mondopack_hydro
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If we can say that around 6 liters is a "medium" saddle bag, then the Relevate is a medium bag that can be pressed into service as a large bag.
The other bags (except marginally, the Ortlieb) are mostly stuck being the size they are. (You can overfill the Carradice "Long Flaps".)