Curb bits are any leverage type bit. It compounds the pressure on the bars of the
mouth by the leverage of the shanks when the reins are pulled. Similar to a pry bar resting on a block or
stone and used to lift an object off the ground.
The full amount of the compounded force of a long shanked bit is much greater (more
severe) than a shorter shanked bit. The longer the purchase of the bit is, the greater the pressure that is put
on the poll area as well as the jaw ( bars of the mouth).
The shank portion of the cheek piece hangs down below the mouthpiece. The reins attach to the
bottom of the shanks.
Another part of the cheekpiece sticks up above the mouthpiece. This is called the purchase. The
headstall is connected to the top of the purchase.
The bit pivots on the mouthpiece between the shanks and the purchase.
As the reins are pulled the shanks rotate to the rear. The bit pivoting on the mouthpiece. As
the shanks move to the rear, the mouthpiece tightens against the tongue and/or bars of the mouth, while the purchase
is pulling down on the head stall against the pole area (behind the ears) and is lifting (tightening) the curb strap
under the chin.
Other than to say "Stop", or "Hey! I want your attention, collect up!" (half halt), a curb
bit has little direct communicative value. All other cues and aids to the horse must be through the laying of the
reins on the neck, leg cues, and body language. That is not necessarily a bad thing.
The beauty of the curb bit is the mouthpiece of a properly constructed bridle bit. It has a port
(or spoon in the center of the solid mouthpiece. This is a curve or "bump up" in the center of it.
When balanced with the correct rein weight and hanging properly in the horses mouth, the horse must
bend his neck at the pole to lower his nose and keep the bit comfortable in his mouth. When his head is held in
this correct position the bit does not bump the roof of his mouth or compress on his tongue.
When the horse bends his neck at the pole (vertical flextion) it puts him in an attentive
and obedient attitude as well as help collect him up. In this way he is able to listen to slight neck rein cues, leg
cues, and body signals of the rider. This enables the rider to ride one handed, freeing up his other hand to do
whatever is required in his work.
So the curb bit automatically keeps him in an attentive frame of mind. A slight lift of the reins to halt or half halt the horse is all that should be required.
A curb bit is a poor choice for an untrained horse. It
is also a poor choice for a horse that will be in high stress situations as it should not be use for direct reining to
turn him or do a proper one-rein-safety-stop.
When you try to direct rein with a curb bit , as you pull on one rein the shank will pull
the horses head that direction, but the purchase part of the bit also pushes back against the horses upper jaw as it
twists in his mouth. This forces him to turn the opposite way as well. Very confusing to the horse. Especially in a high
A curb bit is a good choice for a well trained horse that is at ease in the element that he
Curb bits can have either straight or curved shanks. Curved shanks allow the horse to
carry his head a little higher so as to better see what is going on around him. Bits with these curved shanks are often called
Grazing bits as they tend not to bump the ground if the horse takes a bit of grass.
Straight shanks make the horse carry his head lower and closer to vertical which makes for a more
obediant horse but one that cannot see around himself as well.
Jointed Curb bits:
Some horses fight the effect of the ported curb bit.
They have not been trained into the curb bit and fight against flexing at the poll to find comfort.
The trainer often gives up on its use and uses a curb bit that
has broken or jointed mouth piece instead of going through the proper training methods and steps.
The most notorious of these bits is the TomThumb bit. It is a poor choice all the way
around as it sends the same confusing signals when direct reined as a curb bit does, and it does not require the horse to
bend at the poll for a proper attentive, obedient, attitude. So what you have is a horse that is not required bend
at the poll and no good way to communicate to him. Not a good combination when you get in a tough spot. It combines
the severe part of a snaffle (the jointed mouth piece) with the severe part of the curb, (the shanks).
These bits at first glance look like a D-Ring snaffle bit as they have a D for a cheekpiece.
But in actuality they are a curb bit. They come in most styles of mouth pieces.
On close inspection you will see that the mouthpiece does not connect in the center of the D but
rather up, towards the top corner of the D. Then you will find that there is a short purchase sticking up from the D
that the head stall would attach to. The curb strap is a chain that hangs from the purchase.
The reins attach to the D as in a snaffle but this bit has a slight curb (leverage) effect
when the reins are applied. Some kimberwick bits have uxter slots in the Ds. The reins can attach to these slots to
prevent the rein from slipping up the D when drawn back. This gives the uxter style bit even more leverage.
The advantage of the kimberwick is that it does have some curb action to it and at the same time is
also good for direct reining (if not using the uxster slots). Due to the very low purchase point it does not
twist and give confusing signals when direct reining.
The one down side to the kimberwick is that even with a ported mouthpiece it is not balanced well
enough to automatically cue the horse to bend at the poll. This vertical flextion must be asked for as with a
snaffle bit. They do tend to respond quicker to the flex than with a regular snaffle.
This bit is not necessarily intended to be used with two reins (Pelham style) but it does work
well that way. One rein hooked to slobber straps on the Ds, and the other rein hooked to the bottom uxter straps.
I use sport (rope) reins. My snaffle rein has the center cord pulled out to flatten the rein
and knots are place in it at several measured points. This is tied on to the slobber straps around the Ds. The
round rope curb rein is then attached to the uxter slots.
The snaffle rein is used for direct reining while the curb rein is used to ask for vertical flextion
and, in extreme circumstances, to ask for a stop when other cues are ignored.
A Pelham bit is both a curb and a snaffle bit that simulates a double bridle, but only has one mouth
piece instead of the two bits of the double bridle.
A double bridle is two bridles on a horse at the same time. One head stall is attached to
a bradoon (snaffle) bit ,and the other headstall is attached to a Wymouth curb bit. Sometimes one headstall is used,
but has separate straps coming down to hold each bit.
Each bit would have its own set of reins. They are used simillarly to how I explained in the
The Pelham bit has a purchase and shank that a headstall strap and a set of reins attach
to. It also has a D or O ring centered on the mouth piece. This ring also has a
headstall strap and a set of reins.
Again one rein is used for direct reining and the other is used for neck reining as well as getting
the horses attention with the curb action.
The snaffle rein is usually heavier and wider than the curb rein. ( I use the
rope reins. One flat with knots and one round without knots.)
A Western style Pelham only has one headstall attached to it (at the purchase point) and has a ported
mouth piece. It still uses two sets of reins. Therefore the snaffle reins on it still has a slight curb effect, similar
to a Kimberwick bit.
The English style Pelham usually has a smooth mouthpiece and a double headstall.
In old battlefield pictures you will often see Pelham bits being used on the war horses. George
Washington used Pelhams and double bridles.
A gag bit is basically the English version of a western curb bit. Normally it does not have
a port in the mouthpiece that a western curb bit does. Therefore vertical
flexion must still be asked for by the rider.
It is a poor choice for direct reining. A gag bit's mouthpiece
is usually smooth straight, mullen, or broken, never ported. Sometimes the mouthpiece can slide up and down the
cheekpiece as the curbs are engaged, doubly compounding the leverage.