Curb vs Snaffle Bit
My good friend forwarded to me your email inquiry regarding show bits. I truly believe the show industry needs to change their requirements to allow snaffle bits in order to keep up with the changing times. More and more western riders, like you, are interested in pursuing natural horsemanship and desire to ride their horses in snaffle bits. I did plenty of ranch and cattle work as a working cowboy in Wyoming and always rode with a snaffle bit. It doesn't get any more western than that so if the shows want to be authentic to true western riding they should allow snaffle bits.
So much for my soap box oration on the nonsense of requiring curb bits for western shows, now on to your question. I don't really like the Tom Thumb bit either. It is trying to be a snaffle because it is broken in the middle but it's not a snaffle because it has shanks. It is trying to be a curb bit because it has shanks but it is not a curb bit because it is broken in the middle. Therefore the Tom Thumb bit is neither of the things it is trying to be! If you pull or pick up on one rein using a Tom Thumb bit it tends to have an odd diagonal twisting effect in the horse's mouth which is confusing to the horse and leaves them wondering what you are trying to communicate as well as causing them to move their head all about trying to relieve themselves of the awkward bit movement.
As you know, any bit in which the reins are attached below the mouthpiece (at the bottom of shanks) works on mechanical, vertical leverage. The curb bit in combination with a curb chain or curb strap attached to the bit and run under the chin, actually squeezes the horse's bottom jaw as in a vice whenever the reins are pulled or picked up. Feel the pressure on yourself by placing your fist or forearm between the mouthpiece and the curb chain while holding the top of the headstall up so the bridle hangs vertically then have someone pull back on the reins. You'll discover quickly how painful this can be to the horse's tender mouth. This is true "training through pain and intimidation". You are telling your horse, "If you don't do what I want, I'll hurt your mouth."
A snaffle bit in which the reins are attached directly to the mouthpiece can have no mechanical, vertical leverage but only works on the principal of lateral flexion (bringing the horse's head to the side left or right) which is a much milder and gentler way in which to communicate our requests to our horses. Of course any bit in rough and heavy hands can become a torture device to inflict pain on a horse but at least the snaffle bit is designed to avoid pain.
As far as bit adjustment in the horse's mouth, with any bit I don't like to see any wrinkles at the corner of the mouth. Wrinkles mean bit pressure and bit pressure is a cue which I want to be able to put on or let off from the reins without pressure always being there. I want the bit to fit just at the corners of the mouth without a gap or wrinkles. To truly know how your bit is adjusted, stand directly in front of your horse, grasp the top of the bit where the headstall is attached and pull downward toward the front of the horse's lips then lean over and look at each side at the corner of the mouth to determine if there are any wrinkles or gaps. If you just look at your bit without pulling it down you'll just see how the horse happens to be holding the bit at that moment, not how the bit is truly fitting.
I encourage you to lobby with your show officials to change the rules in favor of snaffle bits! I hope this information is helpful. Let me know how it works out for you and feel free to email anytime with questions.
Enjoy the Journey,
Ed Dabney is an internationally acclaimed clinician, presenting horsemanship and riding clinics all over the US and in Europe. In 2007, Ed was named Champion of the East Coast Trainer Challenge Series by Equine Extravaganza. Ed was honored to have been selected by the University of Georgia to teach their senior level Young Horse Training course.
His training articles have appeared in many major national magazines. Ed produces instructional videos and the “Gentle Horsemanship” TV program which has been seen on RFD-TV.
Ed's blending of natural horsemanship and classical equitation has made an indelible mark with students all across the United States and now also in Europe, drawing the attention of serious riders searching for the lightest touch and the deepest connection with their horses irrespective of breed or discipline.