nav-left cat-right

Fitting Guide

I. Introduction

In order to fit a horse, a saddle must distribute the rider’s weight over as large an area as possible while keeping the withers, spine, shoulders, and loins free from pressure.

The above statement holds true for any type of saddle, treed or treeless. In this guide, we focus on treeless saddles and while the basic fitting premise is the same for treeless saddles as it is for treed ones, some of the particulars are different. Therefore, the information on this page should not be assumed to apply to treed saddles, although some of it may.

Most treeless saddles on the market today work on the principle of a flexible saddle base, with or without rigid elements in the pommel and cantle, that provides spine and wither clearance through built-in panels and/or supplementary padding. This is loosely based on the saddles formerly used by gauchos which consisted of a leather bag stuffed with something along either side of the spine, and a place for the rider to sit on top of that.

Because of the flexibility of treeless saddles, some makers claim that their saddles will fit every horse, but we have not found this to be the case with any saddle design. While a treeless saddle may be capable of accomodating a wider range of horse shapes than a treed one, this does not mean that a given saddle will automatically work for a given horse. Therefore, we have written some basic guidelines for determining whether your treeless saddle fits your horse.

II. Does the saddle provide adequate wither and spine clearance ( String Test section )?

This is the first thing that should be checked and it must be confirmed with the rider in the saddle; because the saddle is flexible, weight in the saddle can make a big difference in how the saddle sits on the horse.

If you cannot get one finger between the pommel of the saddle and the horse while you are sitting in the saddle, stop here and please do not ride in the saddle unless you are able to fix the situation with different padding. The horse’s withers have very little protection and a great deal of damage can be caused by allowing a saddle to rest on the withers, whether there is anything rigid in the saddle in this area or not. If you can get one or more fingers between the front of the saddle and the withers, you can move on to check whether there is clearance along the spine under the entire length of the saddle.

The easiest way to check this is with a simple string test:

  • Start with a piece of thick string such as baling twine, about 3 to 4 feet long, and tie a knot in the string near one end (Fig. A).
  • Then, place the string (with the knot sticking out a few inches at the front of the saddle) in the gullet of the saddle beneath the pad (Fig. B).
  • Place the saddle on the horse and tighten the girth. With no rider up, you should see the knot hanging out under the pommel of the saddle, the other end of the string hanging out under the cantle, and at this point you should be able to straighten the string and make sure it is traveling along the gullet of the saddle, right down the horse’s spine (Fig. C). DO NOT start with the knot already in the gullet of the saddle – if there isn’t much clearance, you don’t want to find this out by getting bucked off.
  • Next, mount the horse, and pull the string through from front to back.(Fig. D) Depending on the material of your pad, the string should either pull very easily through, or require a very gentle pressure to pull it through, and your horse should not react negatively. If you post or stand in the stirrups during your average ride, it is a good idea to repeat the test while standing in the stirrups. If you are using a pad with heat-sensitive (memory foam) inserts, then it is best to ride for a few minutes to warm up the pad before doing this test – these foams will give less clearance when warm than when cold. While riding, tie each end of the string to the saddle or D rings to prevent it from slipping out of place.


String test photo
Figure A Figure B
Figure C Figure D

Interpreting the results of the string test:

  • String slides through easily: OK; no changes needed.
  • String meets very minor resistance that is the same all along the saddle: If you have a fleece-bottomed pad or your horse has a thick winter coat, this is OK. If not, then you may want to increase the thickness or density of your support materials slightly.
  • String meets resistance, but pulls through without a lot of strength needed, or there is mild to moderate resistance only in some areas: A padding change is needed.
  • String will not pull through, or takes a great deal of strength: It may be possible to salvage the fit with padding changes, but another design of saddle with more built-in clearance would be a better option.

III. Are the shoulders and loins free from pressure?

If the saddle extends at all beyond the last rib or overlaps the shoulder blade at any phase of the horse’s movement, then it is important to ensure that there is no active pressure in these areas. A treeless saddle may extend outside the weight-bearing area of a horse’s back, provided that the saddle does not transfer any of the rider’s weight to these areas or interfere in any way with the horse. To find the back of the shoulder blade, it may help to have another person pick up the horse’s foot and bring the leg forward to its full extension. This is the farthest back that the shoulder will come while the horse is moving. If the saddle is well away from this point and also sits in front of the horse’s last rib, then it is OK for that saddle to bear weight along its entire length. If any part of the saddle extends over either of these points, then continue with this test.

Saddle and ride the horse as usual. While sitting in the saddle at a standstill, you should be able to get your hand under the front of the saddle (between the pad and the horse) and feel the back of the horse’s shoulder blade. Your fingers should also be able to slide under the back edge of the saddle. Depending on the bottom material of your pad, it may be hard to slide your fingers under there (100% wool fleece and Sympa-nova are particularly sticky); this is OK, what you are checking for is the amount of pressure you feel once your hand is in there. The type of pressure should be no more than a firm to very firm handshake (keep in mind that it will not be quite as tight for the horse without your hand stuffed in there). Repeat this test at a walk and trot; there may be more or less pressure depending on how your horse carries himself (if he raises his back to move, then there will be less pressure under the front and back of the saddle). If you can feel the horse’s shoulder moving back and forth under the saddle and your hand is not getting uncomfortably pinched, then the horse’s shoulder is not getting uncomfortably pinched either.

If there is pressure in either of these areas, this is the treeless saddle equivalent of a bridging situation. There are several reasons that this could occur:

  1. The saddle is too long for the horse, or the horse has a functionally dippy back (short-coupled with prominent shoulders and hips, or swaybacked).
  2. If there is a rigid piece in the front of the saddle, this is too narrow for the horse.
  3. The contour of the saddle does not match the contour of the horse’s back.
  4. The seat is too small for the rider, and the rider’s weight is being distributed onto the rigid parts of the saddle.

In some cases involving (a) and/or (c), changing the padding or shimming the saddle may solve the problem. We will discuss fitting rigid saddle elements in the next section.

IV. Does the rigid pommel or cantle inserts fit the horse?

Most saddles have some sort of structure in the wither area to provide clearance for the horse as well as shape to the seat for the rider. Most saddles will also have a structure at the back of the seat – this is usually less important in terms of fitting.

Even though none of the rider’s weight should be distributed onto the pommel and cantle of the saddle, these still need to fit the horse properly – an improper fit can result in pinching, rubbing, and indirect distribution of the rider’s weight onto the shoulders and loins of the horse.

The best way to determine fit is to remove the rigid piece from the saddle and place it on the horse in the spot where it will be sitting when the horse is normally saddled. Here are some examples:

Poor-Fitting Startrekk Pommel
Well-Fitting Startrekk Pommel
Poor-Fitting Treefree Pommel
Well-Fitting Treefree Pommel

At this point, don’t worry about wither clearance because once the pommel is back in the saddle, it will be lifted up away from the withers in most cases. If you use wither clearance to determine the proper width for the horse, a horse with high withers will almost always end up fitted with a pommel that is too narrow.

Looking only at the photo on the left, one might think this pommel is a pretty good fit for this horse. However, if we draw a line along the angle of the pommel, we can see that the pommel is in fact way too narrow. It is tempting to fit a wide horse with high withers with a pommel (or saddle tree) that is too narrow in order to provide adequate wither clearance. In fact, you can see that along this horse’s spine, there is scarring from previous lack of clearance with treed saddles. However, this will only cause pinching of the muscles behind the horse’s shoulders and further atrophy, not to mention a lot of discomfort for the horse.
The proper course is to fit the horse with a pommel that matches the angle of his body and build up the saddle with padding to get spine clearance (this would be true with a treed saddle as well). As you can see, in this case it may take a fair bit of padding to accomplish this, but after correct riding in a wide-enough saddle, his muscles will regenerate and the extra padding can be gradually removed.

The angle of the pommel must fit the horse’s body and, later on, padding can be adjusted as needed to lift the whole saddle up away from the withers.

In general, if a horse is between sizes, it is best to fit the horse with the wider size – it’s always possible to fill in extra space with padding or shims, but it is not possible to prevent a pommel that is too narrow from pinching the horse.

The next step is to check for tightness under the pommel and cantle while the rider is in the saddle. Since this was discussed above, we won’t go into detail here, other than to say that if there is pressure under either element it may be possible to eliminate that pressure on saddles with zippered pockets holding the pommel and cantle. The rigid pieces can be removed and the pockets stuffed firmly with material such as saddle flocking, cotton batting, rags, or small bits of foam. This will also work for horses that do not like anything rigid, or that are built too wide for the widest pommel size.

V. Adjusting the moveable panels on the Startrekk saddles

There is a large range of adjustment possibilities for the Startrekk panels. We are available by email or phone to handle specific fitting concerns.

The panels have two main functions:

  1. To keep the withers and spine free from pressure.
  2. To distribute the rider’s weight as much as possible.

Therefore, where the panels are placed will vary depending on the shape of the horse, weight of the rider, and whether the saddle needs to be leveled. To level the saddle, the panels may be moved closer together at the end of the saddle that needs to be raised, or further apart at the opposite end. However, there is a limit to how far the panels can be moved – they should not be moved so far apart that they no longer provide spine clearance, and they should not be moved any closer together than 3″ for most horses, to avoid impinging on the spine from the sides.

The panels should be positioned such that the outside edges extend just beyond where the horse’s back starts to drop off. This prevents the outer edges from digging into the horse where the rider’s legs and the stirrup leathers go over the sides. It also means that on a very wide horse, the panels may need to be placed very far apart, and this could make the rider feel stretched too wide.

VI. Selecting a pad

The pad is a critical part of the saddling system for a treeless saddle, and as such it should be selected as carefully as the saddle for each situation. A pad for a treeless saddle, regardless of design, should always have a flat/non-bulky seam along the spine. Since it is likely, particularly on a make of saddle without panels, that the saddle will not be clearing the spine by as large a margin as a treed saddle would, it is important to minimize bulk in this area as much as possible. The pad should also have adequate contour to prevent it from being pulled down across the withers.

For most treeless saddles, it is desirable to use a pad with pockets on either side of the horse’s spine that contain inserts to lift the saddle away from the spine and to provide the horse with additional protection. If the saddle has panels, then the inserts should be of a material that is complementary to the panels (i.e., if the panels are a closed-cell foam, which is excellent at providing clearance but not as good at providing shock absorption and dissipation of pressure points, we would choose inserts such as Skito foam that provide excellent cushioning and amelioration of pressure points). If there are no panels, then the pad inserts are doubly important, since they must perform the function of providing spine and wither clearance as well as cushioning. Often, in this situation, layering different materials is the best choice – always use the softest material closer to the horse, and the firmer materials closer to the saddle.

VII. Weight distribution

One of the most common criticisms of treeless saddles is lack of weight distribution. While this may have been true of some early designs, there are many treeless saddles on the market now that distribute the rider’s weight as well or better than an average treed saddle.

Another common criticism is that treeless saddles put the rider’s weight on the horse’s spine. As discussed above, this should not be happening with a properly fitted treeless saddle. In cases where damage from wither pressure has been reported, this is due to improper fitting and padding of the saddle, or an inappropriate saddle choice for that particular horse. In most cases it is possible, with the right combination of saddle design and padding choices, to spread the rider’s weight over as large an area as under a treed saddle. The shape of the area and the location on the horse’s back, however, may be different.

VIII. Getting help

We are available via e-mail or phone for consultations on the fit of any treeless saddle, whether we sell it or not. We will be able to provide the best assistance if we have the help of photos and/or wither tracings of your horse.

The most important views for photos are a view straight on from the side of the horse that shows the horse’s entire back, and one from above and behind (have someone hold the horse facing away from you as you stand on something).

Wither tracings should be taken in a minimum of three locations: 1) about an inch in front of the back of the shoulder blade (on top of the shoulder blade), 2) 3″ behind the shoulder blade, and 3) another 3″ behind that. Use a flexible curve or a piece of wire and trace the shape it makes at each location on the horse (trace the INSIDE of the curve) onto a piece of paper. These can be faxed, mailed, or scanned and e-mailed to us.