One of the tricks to getting a good electrolyte balance is eating less salt in your daily diet. It turns out that the more salt you eat, the more salt you sweat and thus have to replace. And salt isn't the only electrolyte you need. You also need calcium, magnesium, potassium, and manganese. On a hot day, I'll take about 80mg of sodium an hour and about same for the others, except for manganese, only .5mg. To make this all very easy, I take Hammer Endurolyte capsules. I carry them in a little coin purse up my shorts leg. Most rides of even 4 hours, if it's not warm, don't need them. If it's hot, maybe 2 an hour if I'm doing a lot of climbing. Anyway, that's not a lot of salt or anything else. There are 2325mg of salt in 1 tsp. So mostly, you don't need anything except water as long as you don't drink too much of it!
I don't drink to thirst, not reliable. I drink to pee, that is once every 3 hours on the bike. If I can't pee after 3 hours, I drink water and take Endurolytes until I do. Also if my HR gets higher than it should for my effort, that also means I need to drink. If it's too low, I need to eat. It's not that complicated if you follow rules like this. It helps that our bodies are really good at regulating all our electrolytes all by themselves.
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