I'm no Dr. but 215 BPM seems pretty high. I actually have a conditional mild tachychardia where my HR will increase to a rapid rate for a brief period of time until I can contain it with breathing exercises. Luckily this doesn't happen when I'm on the bike. During these spells my HR rises to 215+ BPM and I feel like snuffing it (I'm 32 BTW).
Some may argue, but the standard for figuring out a quick and dirty max HR seems to be taking 220 - your age. Under that calculation 197 BPM would be normal for a 23-year-old. Again, I'm not a Dr. nor do I play one on TV so take my response with a grain of salt. I do know that HR is a very personal and unique number that cannot be issued an arbitrary ideal.
I'd consult a physician or cardiologist if you are concerned about it.