I bring powdered versions of my sports drinks on my long distance rides, but not on my tours. On a long distance ride, I've often got a time limit, a speed I need to maintain, so I don't have time to be mucking about in too many convenience stores, grocery stores, etc. to pick something out, so carrying my drink powder of choice is more convenient, plus I know it works for me.
But a tour is different ... I'm not on a time limit so I can ride at a more relaxed pace and can take the time to wander through a grocery store or whatever. On a tour, I will usually have a either two bottles of water on board, and then will pick up an orange juice or coke or something at lunch or other breaks, or I will have one bottle of water and a bottle of some sort of soft drink. I rode around France in 2007 with a bottle of water and a bottle of Orangina.
If you want to flavour your water, rather than bringing a couple pounds of ziplocked gatorade, pick up drink crystals in the grocery stores you stop in at lunch or late in the afternoon before you head to your campsite. If you tour in Canada, stop in at a Superstore now and then. Superstore's store brand is President's Choice, and in the President's Choice brand, you can get "singles" with electrolytes in a variety of flavours, called PC Cool Delight. Each box contains 6 "singles", and last I checked, I think they went for about $1.50 per box ... so $1.50 for six 750 ml bottles.
This is the lemon-lime:
http://www.presidentschoice.ca/LCLOn...roductId=19637
They've also got Tropical Fruit, Pomegranate Blueberry, Fabulous Fruit Punch, and Lucious Orange:
http://www.presidentschoice.ca/LCLOn...s=108&next=25&
Perhaps you can find something similar in other stores as well. They don't have any calories, so if you want your drink to contain calories, then I'd recommend swinging by a wine making establishment and picking up a small baggy of maltodextrin. I often created my own drinks by throwing a scoop of maltodextrin into a bottle, adding one of those "singles", adding water ... and there you go! The last time I bought a 250 ml baggy of maltodextrin, it was $1, and that would do about 6 bottles too. Adding the price of the "singles" to the price of the maltodextrin and dividing by 6 works out to about $0.42 per bottle.
If you can't find something like these "singles", get a small container of HalfSalt. HalfSalt is a potassium/sodium blend ... your major electrolytes. Make your drink as above with the maltodextrin, but instead of the "singles", sprinkle a bit of HalfSalt into the bottle. You can also use it to salt your food, so it does double duty .... and it isn't very expensive. If you want flavour, pick up a packet of koolade or similar for a few cents and add a dash of it to the mix. When I've done this, I like the grape flavour.
Unless you are touring in a remote area, you should be able to pick up this stuff every few days along the way so you don't need to carry 2 lbs of powder with you. Go to your local grocery stores and have a look at what's available where you currently live ... it might give you some idea of what you might be able to pick up along the way.
I also get my electrolytes from the food I eat. I eat a variety of food on my tours, and make sure to salt my meals (often using HalfSalt, as mentioned above).