Good advise....first a horse must learn to respect your clues or commands at walk, trot, lope, etc. Stronger bit is not the answer.
My friend and I, who go out on the trails ALL the time, practice things that we could practice in the ring...like bending and expanding and reducing the trot. So in helping those "brakes", try to keep your horse's mind occupied and more focused on you.
I AM A BIG TRAIL RIDER, AND I HAVE STARTED TEACHING MY HORSE BARRELS AND POLES. THERE IS NOTHING WORSE THAN FEELING LIKE YOUR HORSE WONT STOP. I WAS HAVING THIS SAME PROBLEM A WHILE BACK. MY HORSE ENJOYS GOING FAST, AND HE DIDNT REALLY WANT TO STOP OR SLOW DOWN. HE JUST IGNORED THE BIT I WAS USING. THIS MADE ME A LITTLE SCARED BECAUSE HE IS A FAST HORSE. NO MATTER WHAT I WOULD DO OR TRY HE WOULDNT LISTEN. HE DIDNT WANT TO BE AWAY FROM THE OTHER HORSES ON THE TRAIL. SO I GOT A NEW BIT, I NOW HAVE A MIKMAR FEATHER BIT. IT HAS WORKED WONDERS AND WAS WELL WORTH THE MONEY! WE DO SLOWER "EXERCISES" BOTH ON THE TRAIL AND IN OUR YARD, (I DONT HAVE AN ARENA). WE HAVE DAYS OF RIDING SLOW, AND DAYS OF RIDING FAST. I HAVE BECOME CONFIDENT, AND BEEN ABLE TO ENJOY MY HORSE MORE. IM SURE HE WOULD LIKE TO GO FAST ALL OF THE TIME, BUT HE NOW LISTENS TO WHAT IM ASKING OF HIM AND HE PAYS BETTER ATTENTION TO ME. WE REALLY HAVE A GOOD TIME! PLUS OUR OVERALL RELATIONSHIP HAS IMPROVED SO MUCH. WHEN I CANT RIDE THOUGH, I LUNGE HIM. LUNGING MIGHT BE A GOOD PLACE TO START WITH RESPECT AND COMMUNICATION. EVEN IF YOUR HORSE CANT LUNGE WELL, AS LONG AS HE MOVES FORWARD WHEN YOU ASK, AND STOPS WHEN YOU ASK, HE WILL GET BETTER WITH TIME. JUST USE THE SAME VERBAL CUES THROUGHOUT EVERY SESSION, AND WHEN YOU ARE ON HIM. (KISSY SOUNDS, CLUCKING, ETC.) LUNGING MAY REALLY HELP. IF YOUR HORSE IS AT A CANTER AND YOU GET HIM TO STOP ON THE LUNGE LINE IN ONLY A HALTER, YOU HAVE REALLY IMPROVED YOUR RELATIONSHIP. IF HE TURNS TO YOU AND LICKS HIS LIPS, HE IS REPSECTING YOU AND LOOKING AT YOU AS THE LEADER! THATS GREAT! MY HORSE IS NOW LEARNING TO NECK REIN. I DONT HAVE TO GET IN HIS MOUTH NOW, LIKE I WAS WITH THE OTHER BIT. HE DOESNT RESIST THE BIT NOW LIKE BEFORE EITHER. YES, I AGREE YOU SHOULD HAVE A RESPECTFUL RELATIONSHIP WITH YOUR HORSE, BUT I BELIEVE YOU HAVE TO TAKE DIFFERENT STEPS WITH DIFFERENT HORSES, FOR THEM TO REALIZE YOU ARE THE LEADER. THEY ALL ARENT THE SAME YA KNOW! YOU JUST MAY HAVE TO GET A DIFFERENT OR A MORE HARSH BIT. BUT THE 4 POINT MIKMAR BIT (WHICH IS WHAT THE FEATHER BIT IS THAT I USE) ARENT SUPPOSE TO BE HARSH, THATS WHY I WANTED TO GIVE IT A TRY. I JUST FEEL SAFER AND IN CONTROL NOW, AND MY CONFIDENCE HAS WENT UP DRAMATICALLY. EVEN AT A FULL GALLOP HE SLOWS TO A CANTER OR STOPS WHEN I ASK, WHETHER WE ARE IN A GROUP OR NOT! IF YOU FEEL UNSAFE, DO WHATEVER YOU THINK WILL MAKE YOU FEEL SAFER. I THINK THATS THE KEY. IF YOU ARE UNCONFIDENT, AND UNEASY, YOUR COMMUNICATION WITH YOUR HORSE WILL BE A MESS. IF YOU GET NERVOUS WHEN YOUR HORSE PICKS UP THE PACE IN A GROUP, THAT MIGHT BE WHAT IS TRIGGERING HIS ENERGY, YOU NEVER KNOW. JUST REMEMBER, IF YOU ARE CALM AND FOCUSED, YOUR HORSE WILL BE TOO. I HOPE YOU FIND THE SOLUTION, GOOD LUCK! (YOU SHOULD REALLY CHECK INTO THE MIKMAR FEATHER BIT!)
I HOPE I DINT OFFEND ANYONE, BUT MY COMMENT BELOW IS JUST MY SHEER OPINION FROM MY EXPERIENCES. I INTENDED NO HARM, OR TO UPSET ANYONE. I APOLOGIZE IF YOU FEEL THAT WAY.