The Bridle Wars Part 3: Understanding Mouthpieces

The other important part to understanding bit action is understanding how the mouthpiece of a bit will function. There is one relatively reliable rule: with the possible exception of horses with low palates, the thinner the mouthpiece the more severe the bit's action. This is because the pressure will be concentrated over a smaller area.

Please note that this post is restricted to solid smooth metal bits with no twists or coatings. Twists or chains make for a severe bit, one that I feel is more likely to be abusive than to prove helpful. Rubber bits and rubber coatings have the opposite effect and make a bit softer and more forgiving. I am not a fan of these, (see Part 1: Not A Happy Mouth) though they do potentially have their uses.

There are many different mouthpieces even given our restrictions, but as a general rule we'll break it into four types: solid (aka mullen mouthed), ported, single jointed, and double jointed.

A solid mouthed bit will apply the most pressure to the horse's tongue. As a general rule a solid mouthed bit is a mild bit. It is a good option for horses that have a low pallet as there is no way this bit can poke the horse in the roof of the mouth, an action that can cause the horse to throw his head in the air. There are however horses that dislike tongue pressure and will fight a bits of this style.

A ported mouthpiece is less common on snaffle bits, and more common on leverage bits. A ported mouthpiece will apply less pressure to the horse's tongue and more to the bars of the mouth. This can be helpful for a horse that resents tongue pressure. This also makes the bit more severe because the pressure is being concentrated in a smaller area. The higher the port the more pressure is transfered, and the more severe the bit. A bit with a very high port can also create pressure to the palate (roof of the mouth) as the bit rotates. As mentioned above, this may not be desirable. There is an additional issue with the curb chain leverage action of many ported bits that rather than manifesting palate pressure as head tossing, the horse will learn to break unnaturally at the poll to minimize pressure from both the port and the curb chain. This can result in a horse that carries himself behind the bit, or false carriage in which the horse's head set gives the illusion that the horse is on the bit and carrying himself, when in reality his body may be all over the place. Prolonged work in such a frame can create poor muscle development, and undesirable balance.

A single jointed mouthpiece relieves some of the tongue pressure of a solid mouth, and can apply more pressure to the bars of the mouth. It is generally a mild bit and is widely available in all snaffle varieties. The one caveat with this style of bit is that it can create a severe pressure point on the palate. In horses with a low palate, this may result in head tossing.

A double jointed mouthpiece is generally considered the mildest bit as it most evenly distributes the pressure of the bit across the horse's jaw. It also minimizes the likelihood of pressure points on the palate. However, this type of mouthpiece also adds an additional variable. The center link is highly variable. As a general rule, the larger and smoother the center link, the milder the bit. The sharper or smaller the middle link, the more severe the bit. For example, a bit with a big round oval style center (as pictured at left) is likely to be very mild, a french link with a small center link less so, and a dr. bristol with a center plate set on edge (so that in use the narrow edge of the center link puts severe pressure on the tongue) is much more severe. So think carefully about how the center link will function before you make any judgments about the way the bit will function.

The Bridle Wars Part 2: Understanding Leverage

There are a million bits out there, so many that the latest Dover catalog devotes a full 7 pages to them, and Dover by no means carries every bit in existence. However, there is a trick to understanding the function of every one of those bits. Most bits are a combination of one of a handful of ring designs and one of a handful of mouthpiece designs. Understand those two handfuls and you can make a pretty good guess at what any bit will do. In this post I discuss ring design and its impact on leverage.

When we refer to leverage with regards to bit design we usually are referring to the application of pressure to the bars of the horse's mouth, the horse's poll, and if a curb chain is used, to the horse's chin. The more pressure in more places, the more force a rider can exert to stop, collect, or otherwise adjust a horse's forward movement. How much pressure is exerted is a function of how far apart the minimum distance is between the mouthpiece (Point C) and the cheek piece (Point A) and how far apart the minimum distance is between the mouthpiece (Point C) and the rein (Point B).

In the diagram above with a loose ring snaffle there are no fixed points (all three points can rotate freely around the ring) therefore the minimum distance in theory could be zero. As a result a loose ring gives the least amount of leverage of all bit designs. In an eggbutt, dee ring, or full cheek design the mouthpiece is fixed while the cheek piece and rein can move. This offers very slightly more leverage, but not enough that most riders would notice a difference in the horse's response. So why do we bother with eggbutts, dee rings or full cheeks?

The primary advantage of an eggbutt is purely that it cannot pinch the corners of the horse's mouth, which can be a problem with a loose ring, particularly if the bit is either the incorrect width or adjusted too high or too low in the horse's mouth. Full cheek snaffles were created to apply pressure on the outside cheek when the inside rein recieves pressure. This can be an advantage for a green or stubborn horse. Dee ring snaffles also apply pressure to the outside cheek, but because the ends are connected they cannot get hung up on anything. This makes them safer when riding with others or riding at speed.

But what if we want more pressure than a loose ring, eggbutt, dee ring, or full cheek will provide? To increase the pressure we must fix additional points. An unusual bevel ring fixes the cheek piece and the rein and allows the mouthpiece some limited movement. As the rein is tightened in the rider's hand, backward pressure is applied to the horse's mouth, and if sufficient pressure is applied to the rein to rotate the ring downward pressure will then be applied to the horse's poll. This makes the bevel an intermediary bit between the previous four types discussed and the increased leverage bits to follow. Still need more pressure?

The baucher fixes the mouthpiece and the cheek piece and leaves the rein with a small degree of movement. The greater fixed distance between the mouthpiece and cheek piece creates simultaneous backward pressure upon the horse's mouth, and downward and slightly forward pressure on the horse's poll. This combination of leverage is useful in stopping a horse who tends to pull, or in creating collection.

The elevator bit, sometimes seen with only one lower ring and called a show jumping bit is similar to the bevel in that the cheek piece and rein are both fixed and the mouthpiece has some limited motion. It's action is similar as well. Pressure is primarily upon the horse's mouth if applied lightly, if increased pressure is applied, the pressure is also applied to the horse's poll. However especially if the lowest ring is used the elevator will apply many times the pressure of the bevel because the distance between the cheek piece and the mouthpiece and the mouthpiece and the rein are much greater. A longer lever = more pressure. A variation on the elevator bit is the wonder bit.

What if we want even more leverage? The introduction of a curb chain running under the horse's chin applies pressure in a third place. In a kimberwicke the pressure is the least, similar in action to that of a baucher with the addition of upward and forward pressure on the chin when the rein is tightened. A weymouth has much greater pressure, similar in action to an elevator with the addition of upward and forward pressure on the curb chain.

It should be noted here that weymouths because of their severe pressure should never be used as a single bit. They are for use in double bridles along side a bridoon (a thin mouthed loose ring). As part of a double bridle the primary action is that of the bridoon with the weymouth being used to enhance the riders ability to collect the horse.

A pelham is something of a two in one bit intended to mimic the action of a double bridle when rigged with two sets of reins, one attached to the large ring, one to the lower ring. If used with one rein attached to the large ring its action is similar to a kimberwicke, if that single rein was attached to the lower ring (not recommended) its action would be similar to the weymouth. It can also be used as a kind of false double bridle by connecting the reins to converter straps that buckle onto the large and lower rings, causing the single set of reins to act upon both sets of reins. (See image at right.) The action of such an arrangement would be similar to that of a kimberwick, although with greater leverage.

The Bridle Wars Part 1: Not A Happy Mouth

A personal annoyance of mine lately has been happy mouth bits. There is nothing inherently wrong with these bits, and I'm sure they have been a great innovation for some horses. But I think they are being over used. I dislike happy mouths because most horses I've ridden wearing them lean on them and/or fail to yield to them. I know, silly me, I like to have the brakes installed on all horses I ride.

Many people seem to get happy mouth bits because their horse is green and/or stiff in the jaw and neck. They are hoping that this "milder" bit will encourage the horse to relax and work the bit. Perhaps, but I have two questions for them: if the horse reacts by taking stronger contact is he relaxing or simply finding a new point to brace against? Furthermore, if your horse is stiff in the jaw and neck is it the problem or a symptom of something else? Is he perhaps lacking strength, balance and/or suppleness in his back and haunches that makes him stiff in the bridle? Mild is good, but milder is not always better. Bits are not supposed to be toys, they are a communication tool and horses should be taught to respect them. A horse taught to respect a basic snaffle early in life will be much less likely to be over bitted later in life.