Going from a coughing fit 10 miles to a comfortable 50 milers is good going.
The touring equipment topic would be a good start as the classified section, I echo Boffy's comment about experimenting with fuel and rest.
It's entirely possible to do a long ride if you take it easy, drink regularly (otherwise you'll likely to suffer cramp and headache from dehydration), and eat well, the only thing stopping you from going further is sleep.
Going from a coughing fit 10 miles to a comfortable 50 milers is good going.
The touring equipment topic would be a good start as the classified section, I echo Boffy's comment about experimenting with fuel and rest.
It's entirely possible to do a long ride if you take it easy, drink regularly (otherwise you'll likely to suffer cramp and headache from dehydration), and eat well, the only thing stopping you from going further is sleep.