I would definitely suggest an electrolyte replacement of some sort.
I use Nuun occasionally, Heed mixed in with my Perpetuem on long rides, more Heed and less Perp if it's hot. I also take endurolytes regularly on rides, as many as 3 an hour.
You don't want to mess with electrolyte depletion. Usually it'll just leave you feeling blah and result in cramping but if it's really bad it can lead to heart arrhythmias. Been there, done that, not fun. Then there is severe hyponatremia which in extreme cases can lead to death.
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
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