The Left 90* pivot is also known as a PULL TURN. Pull turns are only executed in 90* - no larger.
Here is a great articles with tips on how to help your horse learn the pull turn:
http://www.horsecoursesonline.com/college/showmanship/lesson_five_642.htm
Here is a video example of what a 90* pull turn looks like when executed.
It occurs at 1:15 after she backs her horse.
https://www.youtube.com/watch?v=v8cluEzUZiY
In this video it is at the very beginning
https://www.youtube.com/watch?v=bkT4Z6_xrLk
In this video it is at 0:55 after inspection
https://www.youtube.com/watch?v=zOMzxsKbanI
Also here is a great synopsis of what judges are looking for in Showmanship.
The original can be found at : http://services2.aqha.com/iphonedev/www/sections/sectionIV/rules/464-483/473.html
"CLASS PROCEDURES: All exhibitors may enter the ring and then work individually or each exhibitor may be worked from the gate individually. When exhibitors are worked individually from the gate, a working order is required. The following maneuvers are considered acceptable: lead the horse at a walk, jog, trot or extended trot, or back in a straight or curved line, or a combination of straight and curved lines; stop; and turn 90 (1/4), 180 (1/2), 270 (3/4), 360 (full turn) degrees or any combination or multiple of these turns. The judge must have exhibitors set the horse up squarely for inspection sometime during the class.
(1) Overall Presentation of Exhibitor and Horse The exhibitor's overall poise, confidence, appearance and position throughout the class, and the physical appearance of the horse will be evaluated.
(A) Presentation and Position of Exhibitor
- appropriate western attire must be worn. Clothes and person are to be neat and clean. The use of any type of artificial aid including, but not limited to lighters, hay, dirt, sharp pins, etc. will be considered a disqualification.
- exhibitors should be poised, confident, courteous and genuinely sportsmanlike at all times, quickly recognizing and correcting faults in the positioning of the horse. The exhibitor should continue showing the horse until the class has been placed or they have been excused, unless otherwise instructed by the judge. The exhibitor should appear business-like, stand and move in a straight, natural and upright manner, and avoid excessive, unnatural or animated body positions.
- the exhibitor must lead on the horse’s left side holding the lead shank in the right hand near the halter with the tail of the lead loosely coiled in the left hand unless requested by the judge to show the horse’s teeth. It is preferable that the exhibitor’s hand not be on the snap or chain portion of the lead continuously. The excess lead should never be tightly coiled, rolled or folded. When leading, the exhibitor should be positioned between the eye and the mid-point of the horse’s neck, referred to as the leading position.
- both arms should be bent at the elbow with the elbows held close to the exhibitors side and the forearms held in a natural position. Height of the arms may vary depending on the size of the horse and exhibitor, but the arms should never be held straight out with the elbows locked.
- the position of the exhibitor when executing a turn to the right is the same as the leading position except that the exhibitor should turn and face toward the horse’s head and have the horse move away from them to the right.
- when executing a back, the exhibitor should turn from the leading position to face toward the rear of the horse with the right hand extended in front of the exhibitor’s chest still maintaining slight bend in the elbo and walk forward. The ideal position is for the exhibitor’s left shoulder to be in alignment with the horse’s left front leg.
- when setting the horse up for inspection, the exhibitor should stand angled toward the horse in a position between the horse’s eye and muzzle, and should never leave the head of the horse. The exhibitor is required to use the Quarter Method when presenting the horse. The exhibitor should maintain a position that is safe for themselves and the judge. The position of the exhibitor should not obstruct the judge’s view of the horse and should allow the exhibitor to maintain awareness of the judge’s position at all times. The exhibitor should not crowd other exhibitors when setting up side-by-side or head-to-tail. When moving around the horse, the exhibitor should change sides in front of the horse with minimal steps and should assume the same position on the right side of the horse that they had on the left side.
- leading, backing, turning and initiating the set-up should be performed from the left side of the horse. At no time should the exhibitor ever stand directly in front of the horse. The exhibitor should not touch the horse with their hands or feet, or visibly cue the horse by pointing their feet at the horse during the set-up.
(B) Presentation of Horse
- the horse’s body condition and overall fitness should be assessed. The hair coat should be clean, well-brushed and in good condition. The mane, tail, forelock and wither tuft may not contain ornaments (ribbons, bows, etc.), but may be braided or banded for English or Western. The length of mane and tail may vary, as long as they are neat, clean and free of tangles. The mane should be even in length or may be roached, but the forelock and tuft over the withers must be left. The bridle path, eyebrows, and long hair on the head and legs may be clipped, except where government regulations prohibit.
- hooves should be properly trimmed and if shod, the shoes should fit correctly and clinches should be neat. Hooves must be clean and may be painted black or with hoof dressings, or shown naturally.
- tack should fit properly and be neat, clean and in good repair.
(2) Performance
- the exhibitor should perform the work accurately, precisely, smoothly, and with a reasonable amount of speed. Increasing speed of the work increases the degree of difficulty, however, accuracy and precision should not be sacrificed for speed. The horse should lead, stop, back, turn and set up willingly, briskly and readily with minimal visible or audible cueing. A severe disobedience will not result in a disqualification but should be penalized severely, and the exhibitor should not place above an exhibitor that completes the pattern correctly. Excessive schooling or training, willful abuse, loss of control of the horse by the exhibitor, failure to follow prescribed pattern, knocking over or working on the wrong side of the cones shall be cause for disqualification.
- the horse should be led directly to and away from the judge in a straight or curved line and track briskly and freely at the prescribed gait as instructed. The horse’s head and neck should be straight and in line with the body.
- the stop should be straight, prompt, smooth and responsive with the horse’s body remaining straight.
- the horse should back up readily with the head, neck and body aligned in a straight or curved line as instructed.
- pull turns to the left should be 90 degrees or less. On turns of greater than 90 degrees, the ideal turn consists of the horse pivoting on the right hind leg while stepping across and in front of the right front leg with the left front leg. An exhibitor should not be penalized if their horse performs a pivot on the left hind leg, but an exhibitor whose horse performs the pivot correctly should receive more credit.
- the horse should be set up quickly with the feet squarely underneath the body. The exhibitor does not have to reset a horse that stops square.
(3) Faults: Faults can be classified as minor, major or severe. The judge will determine the appropriate classification of a fault based upon the degree and/or frequency of the infraction.
