Don’t Be Even a Hole Off! Learn Proper Curb Adjustment

Have you ever had a problem with a horse resisting the bit, turning better one direction than the other or having other troubles accepting rein cues? Improper curb adjustment isn’t often the cause of these issues but it certainly can be the problem. Checking to make sure our curbs are adjusted right when we’re trying to find a solution to these undesired responses is important.

Curb (chin strap) adjustment is correct when the horse gets a signal from the bit as the reins are pulled (feels the bit begin to move) before the curb contacts the chin. Since the curb strap is part of the braking system on your horse you want to be sure the curb makes contact with the chin when you pull the reins. This contact generally occurs within approximately 3 inches of pull on the reins or an approximate 25 to 30 degree change in angle of the shanks after pulling the reins. A good rule of thumb: you should be able to slip a finger or 2 between the curb and chin if adjusted correctly (A). If you’ve made an adjustment in your curb always check before getting on by pulling the reins back to see that the curb makes contact with the chin within 25 to 30 degrees of shank movement (B).

When your chin strap is adjusted correctly this chain of events occurs when the reins are pulled or tightened:

  1. Simultaneous pressure from the mouthpiece is applied on the tongue, bars, lips (and possibly roof of mouth if using a bit with a jointed mouthpiece or port) and to the chin from the curb.
  2. Forward rotation of the bit’s cheek piece ring causes pressure from the headstall’s crown piece on the poll. The pressure on the poll along with the pressure of the bit and curb causes a fulcrum type action to occur.

The pressure points are released when the horse slows or stops and/if the rider releases the pull, or, as the horse’s head becomes perpendicular to the ground and the horse “carries” the bit.

On curb (leverage) bits correct curb adjustment is critical for safety (stopping your horse) and is also important for proper function of not only the bit and curb but the entire bridle. A curb has to be attached to the cheek piece rings or curb rings of the bit. A curb should never be attached to the snaffle rein rings on a bit with shanks because the curb can’t rotate and come in contact with the chin from that position. The curb strap needs to be adjusted so it’s not too loose or too tight. In addition to safety, proper curb adjustment will allow your horse to respond to your rein cues accurately.

When your reins are loose (not being pulled) the curb must lie loose. It should not make contact with the chin unless your reins are being tightened. A curb that is adjusted too tight is uncomfortable and may cause your horse to throw his head or to set his head below the vertical in an attempt to escape the constant tightness. In either situation you lose the effectiveness of your curb.

Riding with your curb properly adjusted will help to make your rides safer and to keep your horse happy, relaxed and ready to give you his best.

I make 9 styles of curbs for a variety of purposes. Visit to see them and their descriptions. For more information on their use visit my AQHA Article “Curb Your Enthusiasm: If you have questions call or text 817-312-5305 or write to me at [email protected]

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