Do you know exactly how your horse’s bit acts on his mouth in response to rein pressure? Many riders don’t. I’m always surprised by the many people I encounter at my clinics (and even at some of the big shows) who don’t have a thorough understanding of how a bit’s design and action work in response to pressure.

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Every horse’s mouth is shaped a little differently, and these slight variations play a role in how a bit acts on his chin, bars, and lips. A bit that works comfortably for one horse might be ineffective and downright painful to another—poking, pinching, or rubbing. This not only makes for an unhappy and potentially unhealthy horse, it also diminishes your ability to communicate with him through your rein cues—whether you’re in the show ring or the practice pen, or out on the trail.

Problem #1: The Strap That Binds

The culprit: In a shank bit, this problem arises from the way the chin strap attaches to the bit and causes the mouthpiece and the strap to interact. When rein pressure is applied, certain configurations cause the chin strap to pinch the corners of a horse’s mouth, between the strap and the mouthpiece. Depending on its placement, the chin strap’s buckle can cause even further pinching in this area. If consistently used in conjunction with harsh hands, this bit setup could cause sores or even tearing at the corners of your horse’s mouth.

Horse’s reaction: Head tossing. If you use this type of bit/chin-strap combination and notice that when you apply rein pressure your horse throws his head up, pinching is likely the cause. Over time, your horse’s discomfort will prevent you from effectively communicating with him, because he’ll constantly try to evade the bit to escape the pain. Riders often attribute head tossing to bad behavior and exacerbate the problem with harsher rein pressure or using a tie-down.

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Considerations: This problem isn’t always predictable—meaning, you won’t be able to recognize this type of bit/chin-strap combination just by glancing at the bridle as it hangs in the tack store. Make an initial pressure test by holding the bit with your hand around the mouthpiece as you apply pressure to the shanks. If the chin strap closes in on the mouthpiece more than what seems right relative to the amount of pressure you applied to the shanks, this bit could be problematic. But you might not be able to tell if this bit will actually pinch your horse’s lips until you try it out on him.

Solutions: If you already use this bit on your horse, try tightening the chin strap a bit so the mouthpiece doesn’t hang quite as low in his mouth. With a snugger fit, the strap won’t hang as close to the mouthpiece as it does when exceedingly loose, and on some horses it’ll raise the shanks up and away from the corners of his mouth enough to eliminate any pinching. Or, if the bit has a short purchase (the part of the bit that extends up from the mouthpiece to where it attaches to the bridle’s leather cheek piece), try using a bit with a longer purchase. If the purchase is too short for the length of your horse’s mouth, it could cause the chin strap to be positioned too close to the mouthpiece, resulting in pinching. Another option is to try a bit that has built-in “slots” (drop-back curb loops) that position the chin strap farther back and away from the mouthpiece and corners of a horse’s mouth.

Try these curb straps; leather curb, chain curb, or link curb.

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Problem #2: Loose Joints

The culprit: If you use a swivel-shank bit or any type of bit with a jointed mouthpiece, and the hinges on the sides of the mouthpiece where it connects to the shanks or the joint on mouthpiece are too loose, the corners of your horse’s mouth can get caught and pinched. Hinges and joints with too much play are typically found in inexpensive, low-quality bits. High-quality bits tend to be made with smoother and more tightly connected hinges.

Horse’s reaction: The pinching caused by loose hinges at the sides of the mouthpiece is similar to the pinching created between the chin strap and the mouthpiece in Problem #1. If there’s too much play in the joint on the mouthpiece, a horse’s tongue could also get pinched. In an effort to avoid the discomfort caused by this pinching action, head-tossing is again his response. Can you blame him?

Considerations: Don’t settle for low-quality bits. Having just a few well-made bits in your tack room is better than a wall covered with cheap, unusable bits.

Solutions: Toss the bit. If your horse generally does well in this type of bit, invest in one with a similar design but of better construction. A basic but well-made, loose-ring snaffle, for example, would be a better option, because the rings go through sleeves that attach to the mouthpiece. These sleeves protect the corners of a horse’s mouth from any excess play in the hinges, eliminating potential pinching. You could also attach rubber bit guards to the mouthpiece where it connects to the shanks. These guards protect a horse’s cheeks and lips from any interference or pinching caused by loose joints. Keep in mind, however, that you can’t use rubber guards in the show ring. If you mostly trail ride or compete in speed events like barrel racing or pole bending, this might be a viable solution.

Try rubber bit guards.

[READ ABOUT: Chin Straps]

Problem #3: A Jabbing Combination

The culprit: A lot of riders use a broken-mouthpiece shanked bit when transitioning a horse from a basic snaffle to a curb bit. (Two examples of this design are a Tom Thumb bit and an Argentine snaffle.) In my opinion, however, if you’re using this as a transitional bit, your horse is still in training. That means you’re likely still riding him with two hands and using direct-rein pressure to ask him to pull his head around to the right or left. Even if you consider your horse finished, but you occasionally use a direct rein to bend his head around in the practice pen or on the trail, this bit is going to create problems.

Let’s say, for example, you use a direct right rein to ask your horse to come around to the right. When you pull your right rein out from your hip to the right, the metal part of the shank that attaches the bit to the bridle is going to jab your horse’s right cheek due to the combined action of this bit’s shanks and broken mouthpiece.

Horse’s reaction: Every time you use a direct rein with this bit, you’ll simultaneously stab your horse’s cheek on the same side. While you’re telling him to bend his head in one direction, you’re also saying, “move away from this poke” in the opposite direction. Anticipating that he’s about to be stabbed in the cheek, your horse might begin turning his head at the mere feel of your the rein. Or he might start tossing his head the moment you mount in an effort to evade any bit pressure, or even plant his legs and refuse to move forward or backward. Consistently giving your horse these mixed messages could create any number of behavior problems, resulting in a downward spiral of miscommunication. And over time, this poking action could cause sores, hair loss, and scarring on your horse’s cheeks.

Considerations: If you don’t have a fundamental understanding of how different bit designs act on your horse’s mouth, go back to the basics and seek help from a trainer or bit professional. You must have a thorough understanding how a snaffle bit works in comparison to a shank bit. A broken mouthpiece doesn’t automatically make a bit a snaffle; a true snaffle doesn’t have any leverage because it doesn’t have shanks. If you apply two pounds of pressure to your reins while using an authentic snaffle bit, your horse is going to feel two pounds of pressure, period. If you apply that same two pounds to a shank bit, your horse is going to feel quite a bit more pressure due to the leverage created by the shanks.

Solutions: You might be able to get by with this bit—if you never intend to ask your horse to bend his head to the left or right! Obviously, I recommend changing bits, as this design will inevitably create problems. Riders often use it because they mistakenly believe it’s a mild, transitional bit due to its broken mouthpiece. Or, unfortunately, the bit and bridle were part of the package when they bought the horse.

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Robin Gollehon trains horses and coaches riders, specializing in Western pleasure and yearling longe line. She and her husband, Roger, own and operate Gollehon Quarter Horses in Versailles, Kentucky (gollehon.com). Robin thanks her models, Apryl Kapfhammer and Born To Be Amazing.