Q: My dressage horse is 17 hands plus, and I can’t seem to find just the right bit size to fit him. Is there such a thing as a custom-made bit? How does it work and where do I get one? 

Name withheld by request

Beth Haist 

A: Yes, there are individuals and companies that make custom bits. But there are also a wide variety of bits available that may not commonly be found on tack store shelves. They may be suitable for your horse, and save you the expense of a custom-made bit. 

First, you need to be armed with your horse’s information, including his exact measurements and his mouth’s composition and palate. To measure your horse’s actual mouth size, you can use a simple cloth measuring tape. Place it in the horse’s mouth in the bit position, and jot down the outside width. Next, measure the width of the jawbones (from outside to outside) underneath the jaw. These measurements will determine the size bit you need for your horse. 

Now you will want to determine what type of mouth your horse has, and judge the thickness of his lips and the shape of his palate because these factors also play an important role in selecting a bit that fits. Gently hold your horse’s lip between your thumb and forefinger to determine the width of the lips. Do this at the top of the mouth where the bit sits.

Next, open your horse’s mouth and look at his tongue to determine if it is thick or average and note the shape of his palate. Notice whether it is flat or cupped. Many warmbloods have lips that are 1ó to 2 inches in thickness with tongues that are equally thick. Compared to lighter breeds, such as Thoroughbreds, these thicker-mouthed horses may need a thinner bit to fit comfortably in their mouths. Using a thick curb and/or snaffle with the intention of it being milder may backfire because these types of horses need space to keep their mouths closed and the bit comfortably wet. 

Armed with this information and your horse’s bitting history, visit a knowledgeable professional at a tack store. He will be able to help you determine the correct-size bit and other important bit-design features based on your horse’s size and mouth composition. While he may not have the bit you need on the shelf, it is highly likely that he will have access to what you need. A wide variety of off-the-rack bits are not commonly found in tack stores.

If you are sent to a custom bit maker, be sure to bring the latest U.S. Dressage Federation Rule Book information on what bits and sizes are legal for dressage. It is your responsibility to have legal equipment should you choose to show at a recognized dressage competition.

Beth Haist is the owner and operator of The Horse of Course, Inc., a full-service tack shop that is a fixture at many of the nation’s top dressage competitions. She trained with Alix Etherington, a wellrespected bit engineer from England. She and her husband, saddle fitter Marty Haist, have been serving the dressage community for almost two decades (thehorseofcourse).