If you are pointing your toes while pedaling, you are putting more stress on the calf muscles. Try lowering your seat just slightly- split the difference between where it was and where you raised it to, and see if your calves get some relief. I find a lot of my Spinning students ride "en pointe", and I try to cue them to keep their feet flat throughout the pedal stroke for that very reason. You may have to mentally cue yourself while riding. Just add it to your internal playlist.