The curb chain decides how much a leverage bit actually does. Knowing how to fit a curb chain properly means it comes into play when you ask and goes quiet when you soften. Fitted badly, it either nags at the horse all the time or does nothing at all.
A curb bit relies on its chain or strap to work properly. On an English bridle that means the Weymouth of a double bridle, a Pelham or a Kimblewick. On Pelhams and Kimblewicks the chain usually stays on the off side hook, and you fasten it on the near side once the bridle is on.
Universals take a curb strap instead, such as the Sprenger Biothane Curb Strap for Universal.
Put the bridle on with the chain undone on the near side. Then turn the chain on the fixed hook until every link lies with its flat side against the jaw. Never hook it up twisted.
Which link goes on the hook? There is no set number: it is whichever link passes the check below. Slip it onto the near side hook and make sure the chain sits flat in the chin groove, done up evenly on both sides.
Take hold of the bottom rein and draw the shank back. The chain should come into play in the chin groove when the shank is at about 45 degrees. Sprenger, who make bits, put the ideal between 30 and 45 degrees, so 45 is the loose end of the range rather than a minimum. As a cross-check, with no pressure on the rein you should be able to fit two fingers between the chain and the jaw.
If it presses the moment you lift the rein, it is too tight and the horse gets no relief. If the shank swings well past 45 degrees first, it is too loose: the bit rotates too far, putting more pressure on the tongue, and can hit the roof of the mouth. There is more on two reins and roundings in what a Pelham is used for.
Metal chains come in single and double link patterns. We have found no bit maker’s guidance on which of the two is milder, so don’t choose on link count alone. For metal, look at the Zilco Full Curb Chain or the Fager Curb Chain.
An elastic chain such as the Shires Elastic Curb Chain has more give than metal. Flat leather works well for many sensitive horses: try the Shires Leather Curb Chain.
If the chain rubs or pinches, a soft cover goes over it. The Gel Curb Chain Guard and the Leather Curb Chain Cover are two options.
A lip strap passes through the fly link, a small ring on the back of an English curb chain. It steadies the chain and stops the horse nipping at the shanks. For a replacement, see the Round Lip Strap.
Chains, straps, covers and lip straps are all in our curb chain and lip strap range.
Many of our metal Pelhams, and the metal Fager Kimblehooks, can go out on a 30-day Bit Bank trial, so you can check how the chain sits on your own horse. If you are unsure whether the fit is right, ring our Bitting Specialists on 01405 861800, option 3.