Bit Measure To correctly measure your horses mouth for the correct bit size put it in the horses mouth and lift it to the correct place in the mouth where the bit will sit – just before any wrinkles begin to form mark the bar on both sides just outside the lip crease. This measurement can then be used to determine the size of the bit required. The bit size will differ depending on the type of mouth piece required. Most horses are fitted with bits that are too tight and this just adds more pressure points. With a fixed mouth piece bit the size required is the measured size and with the single and double break bits this should be the measured size plus 10 mm to take into account the set. In addition to this add 5mm if the bit has a loose ring cheek piece. Nothing additional needs to be added for fixed cheek pieces.
