According to this, the real weight carried may vary from the official weight by up to 5+ lbs.
\"Each day\'s official racing program would state: \"A jockey\'s riding weight includes riding clothing, saddle, undergirth, and pad. The weight listed in the program does not include the jockey\'s safety equipment, which consists of the helmet, goggles, safety vest, and overgirth, and may also include a pommel pad, girth channel, and/or chamois. The total weight of this excluded safety equipment shall not exceed five pounds. The saddlecloths, whip, and bridle are not included in the five-pound limitation on safety equipment. The weight of the saddlecloth, bridle, whip, and all safety equipment is additive to and not included in the program weight or announced overweight.\"
Read more:
http://www.bloodhorse.com/horse-racing/articles/30900/chrbs-shapiro-to-testify-on-guild-dealings#ixzz1ST03Egbx