I've used the same bit on Philipe for years. Its a 5" Herm Springer KK Ultra Loose Ring. I clean it after I use it and I generally lube up the horse's lips with a bit of Vaseline before a ride. In other words, my bit fits, and I make sure my horse is comfortable wearing it.
So, then why did my horse suddenly grow to pink/white patches just outside the corners of his mouth? He is taking better contact with the bit--we struggle with much of the typical Spanish Horse issues of extending the neck out to the bit, keeping an open throatlatch etc. That has improved significantly as of late. However, he feels anything but heavy in my hands.
Still, about two days after I noticed the white patches, he got pinches. OOoops! I felt horrible, but I still can't figure out what changed to cause it. Either way, I removed the bit from his bridle immediately. I wasn't ready to not ride him as I'm going on a trip this next week. His metabolism (like mine) requires regular daily exercise to keep his figure.
It was time for some halter riding!
Now I wasn't jumping out there and doing anything crazy. After all, I started him in a halter and he has been ridden numerous times in simply a neck rope. We just hadn't done that it a while. As most may know I spent a good few years studying with Pat Parelli and learning to ride "Freestyle" hence the name of my farm Freestyle Farm. Every day begins with riding on a long or completely dropped rein and ends the same with periods in between to test self-carriage and seat connection.
Anyway, we rode in the halter. Its now been a week of riding in the halter. I decided that it was a fun time to work on some of our skills for Working Equitation. (I'm training to begin competition in that arena, but more on that later) We sidepassed over poles, backed through L's and did walk pirouettes all over the place interspersed with half-passes, opening gates and just a whole load of fun stuff.
Then I got the new bit. It has wings! Okay, that sounds like something else, but it really does. Its a Herm Sprenger, the same KK Ultra mouthpiece but little guards on the side to keep the bit from pinching. Thankfully, in that short time the pink spots turned black again and his skin healed in a day. But, something else happened in a week of bridleless riding.... I re-discovered the true meaning of freestyle, letting the horse carry the rider, move freely, boldly and through his whole body.
Yesterday was an "aaaahhhh" ride. My horse felt so good. (He would probably tell you its because I felt so good) Riding is always a partnership deal.
Lesson learned--spend more time on our freestyle riding. Get out of the mouth and out of the way more often. Do more with your seat, less with the reins..... and always, ride to have FUN!