Identifying differences in bit construction and understanding some of the important principles of bit use will provide an educated basis for selecting bits. The article below explains the different types of bits available so that riders can determine which one is more appropriate for their horses.

David W. Freeman, OSU Extension Equine Specialist

Bits are designed for riders to cue a horse by placing pressure in and around a horse’s mouth. This pressure is used to control the speed and direction of movement. Bit selection is influenced by a variety of factors, including the
style of riding and tradition of bit use, the rider’s ability, the level of the horse’s training and the intended use of a horse.

Certain riding disciplines use one type of bit more than others. For example, stock seat horses are ridden mostly with one hand on the reins, with a curb bit. Conversely, hunt seat horses are ridden mostly in ring snaffles and guided with two hands on the reins.

Bit selection will also vary because of differences in the abilities of horses and riders. Inexperienced or incorrectly trained horses may be confused and respond adversely to the type or intensity of pressure applied by some bits. Similarly, some riders apply inappropriate levels of pressure with a bit, or they apply pressure at the incorrect times.

The objective of this fact sheet is to assist the inexperienced rider in the selection of bits. Identifying differences in bit construction and understanding some of the important principles of bit use will provide an educated basis for selecting bits. Readers are encouraged to continue their education by receiving hands-on instruction from experienced professionals and by reading and viewing the many resource materials that have been developed on training horses. By
doing so, riders will gain a better understanding of the training process and how bit use and selection can assist them in achieving their riding goals.

Bit Nomenclature

Horse Bridles

Horse Bridles

To begin, riders must have a working knowledge of bit construction and design. Some of the more commonly used terms for identifying bits are presented below.

  • Bars: The mouthpiece portion that is located between the shank and port. The bit’s headstall is adjusted so that the bars are positioned to rest on the bottom palate of the horse’s mouth — the lower gum area between the front and back teeth. This gum area is also termed the “bars” of the horse’s mouth.
  • Bosal: Noseband portion of a hackamore. Bosals are made to surround the bridge of the horse’s nose and lower jaws.Bosals are most commonly constructed with rawhide braided around a rawhide or cable core. Hackamores using bosals are commonly referred to as “breaking hackamores” because of their popularity of use with young or inexperienced horses.
  • Bridle bit: A commonly used term for a bit that applies curb or leverage pressure. Broken mouthpiece: Mouthpiece of bit that is hinged or jointed near the mouthpiece’s center. It is most common for broken mouthpieces to have one hinged joint.
  • Chin (curb) strap: A leather or chain strap attached to the shanks of a curb bit. It is positioned under the horse’s chin behind the muzzle. Chinstraps provide the lower boundary point of pressure when rein pressure is applied to curb bits. Most horse show organizations require that chinstraps be at least one-half inch in width and lie flat against the jaw. Usual adjustment allows for release of chin pressure when reins are loose. The longer or more loosely attached the chinstrap is, the less abrupt and intense is applied pressure.
  • Curb bit: A type of bit with a mouthpiece and shanks. The headstall is attached to upper shanks and the reins are attached to lower shanks of a curb bit. Curb bits apply leverage pressure. When reins are pulled, the action of the mouthpiece and curb strap tighten on various locations in and around a horse’s mouth. Curb bit construction is modified to apply varying amounts of pressure on the tongue, lips, bars and roof of the mouth; and, by way of the chinstrap and headstall, under the chin and over the poll on the horse’s head. The poll is the area on top of the horse’s head behind the ears.

examples of curb bits

  • Hackamore: Headstall and noseband designed to exert pressure on the bridge of the nose and under the chin of the horse’s head.
  • Mechanical hackamore: A noseband device with a curb strap and hinged sidepieces. Mechanical hackamores apply pressure around the nose and chin. The main function of a mechanical hackamore is to slow or stop horses, as the design limits lateral pressure even when a single rein applies pressure.
  • Mouthpiece: The part of the bit that lies across the tongue of the horse’s mouth. Bits usually have a single mouthpiece. The mouthpiece is positioned in the horse’s mouth to lie on top of the tongue. Most often, the headstall is adjusted so that the bit’s mouthpiece is positioned to lightly touch the horse’s mouth where the upper and lower lips join. Snaffles may be positioned approximately one-eighth inch to one-fourth inch below this area when hanging freely.
  • Port: Raised portion of solid mouthpieces. Some hinged mouthpieces also have ports. The port places pressure along the tongue and, if high enough, the roof of the mouth. Wider port widths allow for less pressure on the tongue.
  • Pressure points: Areas where bits apply pressure when rein pressure is applied. Pressure points include the tongue, bars, roof, and corners of the mouth; and the nose, poll and chin of the head.
  • Rings: The outer portion of snaffle bits that function to position the mouthpiece and allow attachment of the headstall and reins. Variations in ring diameter and shape influence the location and intensity of rein pressure.
  • Shanks: The sidepieces of a curb bit. Upper shanks extend above the mouthpiece and serve as an attachment point for headstall and curb strap. Lower shanks extend below the mouthpiece to serve as an attachment point for the reins. Variations in bit construction in the length and angle of shanks allow for differences in pressure.
  • Snaffle: A type of bit made of a mouthpiece and rings. Snaffle bit mouthpieces are most commonly jointed in the middle. Because of this, curb bits with jointed mouthpieces may also be termed a snaffle, although the bits actually work by curb pressure. True snaffles are constructed so the bridle headstall and reins are attached to rings positioned on the outside of the horse’s mouth. As such, the bits apply rein pressure directly to the mouthpiece. Snaffle bits place pressure on the tongue, corners of the mouth and the bars of the mouth.
  • Solid mouthpiece: A non-jointed mouthpiece. Solid mouthpieces have bars and ports, which alter the amount and area that pressure is applied.

Types of Snaffle Bits

Select types of snaffle bits
image:Snaffle bits 1.jpg

Variation in Bit Construction

Bits are constructed to vary the location, intensity and type of rein pressure. Some of the main ways bits vary in construction to alter pressure are provided below.

  • Bit balance: altering the placement, weight and shape of the shanks and mouthpiece creates bit balance of curb bits. Bits constructed to significantly release pressure when rein pressure is released are termed “over-balanced.” Bits that maintain pressure without rein pressure are termed “balanced” or “under-balanced.” Balance can be determined by laying an unattached bit on your fingers,which are positioned under each end of the mouthpiece. A bit is over-balanced if the lower shanks of the bit hang forward from the mouthpiece and upper shanks. It is under-balanced if the lower shanks hang behind the mouthpiece. Because it is desirable to have a release of pressure when not cueing, most bits are designed to be over-balanced. Balanced bits are used infrequently, and then only on experienced horses and by experienced riders.
  • Bar elevation: The bar portion of a mouthpiece may extend straight from the shanks to the port or elevate upward and forward. More elevation allows for more area between the mouthpiece and the horse’s tongue.
  • Bit material: Most bits are made of steel, iron or aluminum. Some have mouthpieces made of or inlaid with copper. Other mouthpieces are covered with rubber. Some shanks are engraved or inlaid with precious metals for atheistic value.
  • Mouthpiece diameter: Mouthpiece diameter typically varies from five-sixteenths of an inch and three-fourths of an inch, although there are smaller and larger sizes.
  • Mouthpiece elevation: Distance from the bottom to the top of the port or mid-section of a mouthpiece. Ports with 2 1/2 inches or more of elevation can apply pressure on the upper palate and, because of the sensitivity of this area, should not be used on inexperienced horses or by inexperienced riders.
  • Mouthpiece placement: As viewed from the side, the angle created by the position of the port and the position of the upper shanks. Mouthpiece placement usually varies from the port and upper shanks being in line with one other to the port positioned forward of the upper shanks by about 20 degrees to 30 degrees.
  • Mouthpiece shape: Most mouthpieces are smooth and rounded. Some mouthpieces are twisted, rolled or flattened to cause variations in intensity of pressure.
  • Port shape: Port shape varies from maintaining the mouthpiece shape in rounded mouthpiece bits to being flattened, rolled or covered. The top of the port may be flattened backward to heighten pressure on the tongue or to alter bit balance.
  • Port Size: Port widths vary to allow for differences in the amount of tongue relief from pressure. Port heights vary to allow for differences for tongue relief and pressure on the upper palate.
  • Shank length: Upper shanks are usually 1 inch to 2 inches in length. Lower shank length varies more with commonly observed differences of 3 inches to 7 inches. However, there are several noted exceptions for upper and lower shank lengths.
  • Shank position: When viewing bits from the side, shank position varies from shanks constructed in line with the mouthpiece to positions where the bottom and/or top shanks angle behind the mouthpiece.

Bitting Principles

Bits provide one of the major points of control when riding horses. Knowledge of horse behavior and training principles used to modify behavior must be considered when selecting and using bits. Some of the important training principles related
to bit use are provided below. Readers are encouraged to also review OSU fact sheet F-3915, “Training Principles for Developing Safe Horses,” to supplement the following.

  • Bitting Process: Bitting is a continual process of training, which through repetitive and step-wise training, teaches horses to accept bits and properly respond to bit pressure.
  • Curb pressure: Curbs with longer, lower shanks in relation to upper shank length increase pressure by increasing the leverage of pull. Pressure is intensified on specific pressure points by variations in mouthpiece design.
  • Curb use: Curbs are used primarily to slow or stop horses with pressure created by leverage and to guide horses by using a neck rein cue. Curbs are used on horses trained previously to respond to direct and neck rein cues from earlier training with snaffles and/or hackamores.
  • Ground driving: Ground driving employs the use of long lines attached to a ring snaffle bit. The lines are directed through a bitting harness or saddle to aid in directing the pull from the handler to the horse’s mouth. The handler guides the horse by use of the lines while positioned several feet behind the horse. Horses can be taught to stop, back up and guide with direct rein pressure before ridden for the first time. Ground driving is used with young horses to introduce bit pressure and also as a reinforcement aid on older horses. As with other horsemanship practices, inexperienced handlers should receive hands-on instruction before attempting ground driving for the first time.
  • Hackamore use: Bosal hackamores, similar to snaffle bits, are used in training of young horses in the stock seat discipline. Bosals are used to a lesser extent with older horses, as many horse exhibitions require the use of curb bits with older horses. Mechanical hackamores are used to enforce a stop or slowing action in activities such as roping and speed events. Mechanical hackamores limit lateral pull as compared to snaffles, even when single rein cues are used. Mechanical hackamores are most effectively used on horses with previous training rather than as a beginning bridle.

Bits that increase pressure intensity
  • Pressure Intensity: The goal of the bitting process is to train the horse to respond from as little pressure as possible to perform a given task. As such, cues should employ as small amount of rein pressure as possible. Pressure intensity is heightened when reinforcing a previously applied rein cue. (See OSU fact sheet F-3915, “Training Principles for Developing Safe Horses.”) Applying large amounts of pressure intensity when cueing a horse for the initial response increases the frequency of undesirable responses from the horse and limits the ability of the horse to learn additional tasks. Inexperienced horses should be trained in bits that apply mild intensity and direct pressure instead of bits that intensify pressure or work with leverage.
  • Pressure Release: Applying single episodes of long-term pressure encourages resistance and avoidance of cues. As such, application of bit pressure should be short termed and immediately followed by a release period. If more rein pressure is needed for reinforcement, additional pull-and-release pressure should be applied instead of lengthening the duration of the initial cue.
  • Pre-ride bitting: Horses in beginning stages of training are accustomed to the bit and taught to respond to rein pressure before riding. Familiarizing a horse to the bit is accomplished by several sessions of bridling the horse with a snaffle bit and allowing it to wear the bit for several hours at a time without reins attached. The second objective is to teach the horse to respond to rein pressure. One method is to tie the reins from a snaffle bridle to a bitting harness so small amounts of pressure are applied to the horse’s mouth until the horse responds acceptably. Another method is ground driving. Unless experienced with these methods, readers are encouraged to receive hands-on instruction from knowledgeable people before attempting these pre-ride bitting methods.
  • Snaffle pressure: Ring snaffles apply direct pressure from the reins to the horse’s mouth. Most ring snaffles have jointed mouthpieces to intensify the pressure on the corners of the horse’s mouth. This enhances the ability to pull laterally, thus directly guiding movement by redirecting the horse’s head. Pressure is intensified by using smaller mouthpieces or by rolling or twisting mouthpieces.
  • Snaffle use: Inexperienced horses are taught to respond from a direct pull of the reins. Young or inexperienced horses are expected to require frequent reinforcements following the horse’s response to an initial cue. Snaffles apply a simple type of pressure, direct pull, and, when used correctly, are mild enough to use with frequent reinforcements. English-style riding allows for continual snaffle use throughout use of horse. Most western showing requires that older horses perform in curb bits. Even so, snaffles are commonly used as a training tool throughout the life of horses ridden western because of the advantages of snaffle action when applying frequent reinforcements.

For more information on bits, check out the Understanding Bits Learning Lesson.