The GCN Show on Youtube recently compared the wind-tunnel efficiency of cycling with either a backpack/rucksack, large saddle-bag, or panniers.
I have used a variety of all three of these luggage-carrying techniques (and others) over the years, and while the team, admitting a lack of scientific rigorousness to their tests (while making use of a not-so-cheap wind-tunnel testing facility) failed to take into account a number of other points; including rider comfort, riding style and bicycle type, not to mention covering a variety of luggage weights and sizes. Their video title specifically mentioned “for commuters” but that term is very broad; not all jobs and journeys are the same, and with the aim of being “aero”.
To cut a not so long video short, they ruled in favour of the rucksack. Their results however (unless you match the guinea pig’s example), really just came down to personal preference.
Here is my experience.
If out for just a leisurely ride and not running any errands which require me to carry or collect stuff, then a small and simple saddle-bag with a spare inner-tube and necessary tools are all that are required.
In my younger years I was given an old and larger saddlebag that could pack some waterproofs and a lunch box, and I can imagine that it wasn’t particularly aerodynamic (compared to the GCN team’s example) but this didn’t concern me at the time.
I began using this particular saddle bag more and more during my high-school years in addition to an old but trusty Karrimor rucksack when it lacked the capacity of the ever-increasing demand of my studies. Even then I had to get inventive when my art/graphic design lessons necessitated work in A3 size, and for this I used an A3 zip-locked pocket which I slipped in between my back and my rucksack. Clever huh? This probably stuck out like a pair of wings and would have certainly lacked aerodynamics, but the alternative would have been to roll up my work; something I didn’t want to do.
Through a couple of college years my carrying-demands were much the same, but I did have a couple of larger books to carry, but as I recall I simply put these in my rucksack. A stack of books on the back aren’t as comfortable as the GCN team’s example of packing some spare clothing.
Skip ahead now to some 10 years later and I’ve been through the whole car-driving phase, and emerged on the other side no longer drive a car. I therefore ride my bike almost every day, for work, leisure, and shopping (just as one might use their car) and choosing a touring bike instead of a ‘road bike’ I have the added option of panniers.
Panniers have found me using a rucksack less and less, although in extreme cases (such as when actually cycle-touring) I have used four panniers and a rucksack. With those cases aside, on a typical day my finding is that I prefer the use of a couple of panniers instead of a rucksack and this is mainly for personal comfort; I have noticed that I am prone to lower back pain if carrying a little too much in a rucksack for any number of miles, and a rucksack doesn’t allow my back or shoulders to ‘breath’; there is little point to a breathable jacket if the vents at the back are flattened down and also the straps of a rucksack will tend to wear away the waterproof coating of such a jacket, leading it to lose water repellency and require treatment (another cost).
The GCN test didn’t take these things into account but what they did reveal to me was this. Sometimes I will cycle to somewhere with empty panniers (or just a few things), save for an additional rucksack that I’ll pack in one, in order to bring back, say, more shopping. The GCN findings suggested that it would be more energy efficient, that is, less wind resistant, to pack my empty panniers in my rucksack instead. I have not change my habits to put this into practice though.
Another factor in all of this is cost. The GCN team, as are many ‘keen to behave like a pro’ cyclists out there, typically more higher-spenders than me. While I don’t consider my bike to be particularly cheap (although by some standards if could be), I tend to look at the cheapest options and work myself through the list until I find what I’m looking for without paying a silly amount extra for a particular feature, rather than looking at expensive options and seemingly scoffing at something if it’s too cheap. For this reason, my panniers are actually the cheapest I could find and lasted me five years; they needed some repairs in this time and weren’t waterproof as some can be, but for this feature I just bag up my contents with the plastic bags that the panniers themselves were sent in (#logic). Even some of the more expensive ones aren’t waterproof but why pay many times more something to be waterproof when #1 you can protect your contents with a free alternative, #2 the waterproof protection of panniers, just like rucksacks and jackets, tends not to last anyway. More on this in a moment.
My rucksacks are similar (I have two of different capacities); they weren’t designed specifically for cycling so they’re perhaps not all that aerodynamic, but they hold what I need them to hold, and not being all that expensive, once they start to get a bit tatty or damaged through regular use (as all things do) I will not feel too hard done by when I have to replace them; should I have chosen more expensive items and found them to not last much longer I wouldn’t feel so good.
Here is that GCN video: