I need some help. I did my first outdoor ride of the year a month ago after riding indoors for the winter. My heart rate monitor wouldn't exceed 100 bpm. I rode yesterday and my heart rate ranged from 160 to 170. So all is good. Well, today I rode again and my heart rate, again, wouldn't go over 100 bpm. I stopped and switched from bike outdoors to bike indoors and my heart rate was back to the 160-170 range. Has anyone experienced this or have a solution? I don't use a chest monitor, if that is what you're wondering and I'm up to date on all updates. Further, this was not an issue last summer.