The bit is the smallest piece of equipment your horse wears, but it sits on one of the most sensitive spots on its body. Which bit fits depends less on what's popular at the yard and more on the shape of the mouth, the training level, and how your horse responds.
What a Bit Does (and Doesn't Do)
A bit gives your hand a connection to the horse's mouth, so you can pass on signals and help shape the contact. The bit doesn't work by causing pain; it works through pressure and the release of it. The horse learns that gentle pressure in a certain place is a request, and that the pressure disappears as soon as it gives the requested response.
Pressure is distributed across different spots, depending on the type of bit:
- Bars — the toothless ridges of the jaw where the bit rests.
- Tongue — carries part of the weight and pressure.
- Corners of the mouth — especially with jointed bits that have an upward action.
- Chin and poll — with leverage bits, pressure is added here through the curb chain and the bridle.
A harsh bit isn't a punishment, but a precision instrument. In a calm, practiced hand, a sharper bit can communicate more finely; in an unsteady hand, it does more damage. The hand determines the effect, not just the bit.
The Two Main Families: Snaffle and Leverage Bit
Almost all bits fall into one of two categories.
A snaffle (Dutch: trens) works without leverage. Rein pressure arrives almost one-to-one on the tongue and bars. This is the mildest and most widely used type, and the starting point for most recreational and lower competition classes. In dressage up to and including the higher basic classes, riding on a snaffle is mandatory.
A leverage bit (such as a curb, pelham, or Weymouth) has shanks below the rein attachment. This magnifies rein pressure and adds poll and chin pressure. It demands more riding skill and is only introduced once the horse goes well on the snaffle. In the higher levels of dressage, you ride a double bridle: a thin snaffle (bridoon) and a curb together.
| Family | Action | When |
|---|---|---|
| Snaffle | Direct pressure, no leverage | Basics, young horses, dressage up to medium level, most recreational riding |
| Pelham / kimberwick | Light leverage, one bit | A horse that needs extra brakes, show jumping, driving |
| Double bridle (bridoon + curb) | Two bits, refined steering | Upper-level dressage, experienced combinations (you and your horse together) |
The Mouthpiece: Shape and Thickness
Besides the family, the mouthpiece determines how the bit feels. This is where most of the differences lie.
- Unjointed (straight or slightly curved) — a single bar, presses evenly on the tongue. Calm, but leaves little room for the tongue.
- Single-jointed — one hinge in the middle. Under rein pressure, the center can rise against the palate (the so-called nutcracker effect). The best-selling type.
- Double-jointed — two hinges with a center link; distributes pressure more evenly over the tongue and is more comfortable for many horses.
For thickness, there's a rule of thumb that's often misunderstood: a thick bit isn't automatically milder. A thick bar spreads the pressure over a larger surface, but takes up a lot of room in a mouth that often has little room to spare. Horses with a fleshy tongue or a low palate actually go more comfortably in a thinner, double-jointed mouthpiece. So don't automatically start with the thickest bit.
The material affects saliva production and chewing activity. Stainless steel is neutral and common. Copper alloys and some synthetic materials stimulate chewing, which can help a horse with a dry mouth relax.
The Rings: How the Bit Sits in the Mouth
The type of cheekpiece determines the stability and lateral steering of a snaffle.
- Loose ring — the ring rotates freely through the mouthpiece. Mobile, forgiving, gives the horse room to seek the contact itself.
- Fixed ring (eggbutt) — mouthpiece and ring are fixed to each other. More stable in the mouth and less likely to pinch the corners; calm for young or sensitive horses.
- D-ring and watertrens (a large-ringed snaffle) — give extra lateral steering, since the ring presses against the cheek when turning. Widely used with young horses and in show jumping.
How to Arrive at a Choice
Always start milder than you think you need. Many problems that look like a "too soft" bit actually come from training, balance, or a hand that interferes too much. A sharper bit at most covers such a problem up.
Work through these steps:
- Measure the width. The bit should stick out half a centimeter to a centimeter on each side, without pinching the corners of the mouth. A bit that's too narrow pinches, one that's too wide slides back and forth.
- Look at the shape of the mouth. A short mouth, a thick tongue, or a low palate call for a thinner, double-jointed mouthpiece with enough room for the tongue.
- Rule out pain. Resistance, head-tossing, going against the bit, or putting the tongue over the bit can be related to the bit, but just as easily to sharp hooks on the molars or an inflamed corner of the mouth. Have the teeth checked yearly by a vet or equine dentist before you start changing the bit.
- Change one thing at a time. If you switch the bit and the noseband at the same time, you won't know afterward which one made the difference.
- Ask someone to watch. An instructor can often see within a few minutes whether the resistance comes from the mouth, the back, or the riding itself.
For competitions, follow the rules: the KNHS (the Dutch equestrian federation) sets out per discipline and class which bits are allowed, and not every bit that works fine at home is also allowed in the ring. Check the current competition rules on knhs.nl before you use a new bit in a test (a set exercise you ride for the judge).
In Short
Choose the bit for your horse's mouth, not out of habit or because it seems sharper. Start with a mild, double-jointed snaffle with loose or fixed rings, measure the width carefully, and rule out mouth pain first before changing anything. If it still isn't working after a reasonable training period, have an instructor take a look rather than switching to a harsher bit. The bit refines the communication; it doesn't fix a gap in training.
See also: Which Tack Actually Makes a Difference · Glossary: contact, going on the hand, and the bit · Level: Considering Your Own Horse