Basic Pressures applied by a bit
Interior Pressures
Pressures applied by the mouthpiece of the bit.
Bar Pressure:
- All bits will exert some pressure on the bars. The levels of pressure will vary depending on the design
- Recent patterns show, horses accept bar pressure more than tongue pressure, unless there is some damage to the bars
Effect:
- Encourages flexion in the poll
- Release of the jaw
Squeeze On Bars
- Squeeze is exerted on the bars
- Single and double jointed bits create squeeze
- Semi-broken and cable bits create a limited squeeze
- Solids do not create a squeeze
- Generally well accepted in small amounts
Effect:
- Large amount raises the head
- Small amount extends the neck out
Tongue Pressure
- Most bits will place some pressure on the tongue at some point, pushing it down into the mouth
- Recent patterns show, more and more horses object tongue pressure
- Release of the jaw
Effects:
- Encourages flexion in the poll
- Encourages head to come down and the nose to come in – if pressure is accepted
Exterior Pressures
Pressures applied by the cheekpiece of the bit.
Poll Pressure:
- Pressure is created on the top of the head, behind the ears.
- Poll pressure is created due to a fulcrum effect. When the bridle is attached above the mouth piece and the rein below, the torque on the bridle cheek piece creates poll pressure.
- Longer length of the purchase (shank above the mouthpiece) increases poll pressure
Effect:
- Creates a head lowering effect
Cheek Pressure
- Pressure applied by the cheekpiece to side of the horses face
- Most fixed cheek pieces will, to some degree, apply cheek pressure
- If a bit strap is added to a loose ring, it will also start to apply some cheek pressure
Effect:
- Supports lateral aids by applying pressure to the opposite side of the face (eg. Fulmer)
- Useful for schooling young horses
Curb Pressure
- When a chin strap or curb chain is used with a curb bit, it will apply pressure to the chin groove when the reins are taken up
- Creates a squeezing affect of the lower jaw between the curb and the mouthpiece
Effect:
- Curb chain limits the rotation of the shank
- This must be balanced with the amount of pressure the curb applies
Rotation effect:
- More rotation results in grater leverage on the mouthpiece
And less pressure through the curb
Fit of the curb chain is very important. If the curb is too tight, we will have too much curb pressure, with minimal leverage. If the curb is loose, we will have minimal curb pressure but potentially much greater leverage.
The shank should not be able to rotate past 45 degrees.