Tack shops and equestrian catalogues are filled with all sorts of bits of differing shapes and sizes. Unfortunately, bits are the most misunderstood piece of the horse’s equipment ever invented. Too often, we humans are of the opinion that as our horses are big animals, therefore the pressures needed to control them must be big and strong. This is just not true. If you really take a look and study your horse’s mouth, you’ll see that there are very few surfaces where the bit can apply pressure. The bit must be shaped to fit properly within the mouth so that your horse is able to understand the communication and not flinch from it.
The area in your horse’s mouth where the bit communicates pressure is called the bars. The bars are the gaps between the front teeth and the back teeth on either side of the jaw consisting of tissue-covered, pressure sensitive cartilage. The bit lies across these bars and presses against the horse’s tongue and depending upon the bit’s shape and adjustment, can also put pressure on the horse’s lips, tongue and roof of the mouth.
The first thing you need to look at before you put anything in your horse’s mouth is the contact area. The thinner the bit, the less contact area it has and the greater the pressure on the bars…makes sense. Also makes sense that the thicker the bit, the greater the contact area and the lower the pressure on the bars.
The second thing you look for in a bit is whether it is straight or shaped. If the bit is straight, the horse’s tongue will absorb some of the pressure of the bit and the horse will feel less pressure on the bars of his mouth. If the mouthpiece is hinged, the bit provides more pressure on the bars of the mouth and will in turn give more directional guidance.
The third aspect of a bit to examine is the leverage. The curb bit is different as it has the reins attached below the mouthpiece so the principle of the lever and fulcrum is in effect. This means that if the cheek or purchase piece of the bit is one inch and the shank is three inches, then the bit is 1 to 3 in leverage. What this means is, if the rider applies one pound of pressure to the reins, three pounds of pressure is applied to the horse’s mouth. Typically, as the horse progresses through his education, he is generally asked to work with a curb bit as the lever of the action of the curb bit magnifies the subtle movement of the reins as the rider asks for head and body frame. Use the curb on a horse that knows what to do…knows the positions and has learned the correct responses and understands that by responding quickly and correctly he will be left in a comfortable position. Curb bits are non directional and their pressure is felt as a clamping between the horse’s chin and the bars of the mouth. If you use a chain, the pressure is more noticeable underneath the chin whereas if you use a leather strap, the pressure is more on the bars of the mouth.
The biggest mistake a rider can make is taking only the bit into consideration not thinking that the bit is only a part of the overall passageway of aids, that of the seat and legs, to create the shape you want for your horse. You don’t want the bit to speak louder than your legs or seat and you don’t need a big bit to get your horse’s attention. You just need to know how to use the bit to make it more understandable to your horse.
Too many people rely solely on the bit, saying if the bit doesn’t work, then they’ll try one with a longer shank or one with a thinner mouthpiece or twisted wire! If that doesn’t work, then other artificial aids will control the horse. It is very unfortunate that many people rely on a 5 inch bit and do not measure the horse’s mouth for the proper bit size.
According to Susan Harris, “If a bit doesn’t fit properly, the horse will fuss with his mouth, toss his head or pull.” All bits should be about a half-inch wider than your horse’s mouth and you need to measure your horse’s mouth. Don’t guess at the size! Also, bits must be smooth and comfortable. A true snaffle bit should rest high in the horse’s mouth so it won’t irritate the horse’s tongue, while a curb bit should rest against the corners of your horse’s mouth without making a wrinkle.
Having a bit too low in your horse’s mouth may be problematic as the lower in the horse’s mouth, the bars get thinner and sharper making the mouth more sensitive. You can really irritate your horse if the bit is too low and can especially hurt his mouth if he should get his tongue over the bit.
Also remember that not only is fitting the bit important, but it is also very important to have the entire bridle comfortable and proper fitting.