I have three bottles on my bike, but obviously that is not enough for one day of biking. Any recommendations?
I forgot to mention this in my post above. In addition to the bottles on the frame, you can put two more in one of the holders that goes behind the seat that triathletes use [1]. Originally I got the
Aquarack from
Profile Design but it sat down low and interfered with luggage, so then I got the Saddlewing from
XLab that clamps onto the seat rails and sits up high, out of the way of luggage. You can see it here with my huge (almost two gallons' worth of space)
Mountain Wedge III from
Jandd Mountaineering which I got to carry a few clothes and things for light credit-card tours of a few days where you stay in motels and eat in restaurants instead of carrying your camping gear:
Although one bottle hides the other one in the picture, there are two 32-ounce Zefal Magnum water bottles there. Oh, and I should mention: Do get the Zefal Magnum bottles if your frame is big enough to hold them. Most touring frames are, but sloping-top-tube frames usually won't handle them in the seat-tube cage, even with a side-entry cage, because these bottles are so tall to get an entire quart in them. The kind I have has been discontinued and Zefal now has a
re-desiged one out that holds a couple more ounces. I think some people were complaining of leakage in the old one although we never had any trouble, so this new one may have been to improve that.
With that arrangement, I can start with an entire gallon. I would like to find a way to put another quart under the down tube but I can't safely just hoseclamp another cage down there to the carbon like I did to my old, thick steel frame which cracked anyway--twice--with less than half as many miles of hard riding as I have on this bike.
Twofish has their Quick Cage water bottle cage which just velcros on, but it doesn't go up to tubing as big as my down tube.
[1] The idea there is to make the bottles draft your body to reduce wind resistance; but wind-tunnel tests have found that it's actually beneficial to the aerodynamics to have a bottle in the seat-tube cage even if it's empty, as it acts as a fairing to guide the wind
around the rear spokes. The strangest thing is that it helps more if there's some crosswind component! Obviously water-bottle aerodynamics won't have as great an effect when you have big panniers sticking out catching the wind.