nicci,
If you're experiencing thigh bar rips or scrapings on your thighs on bars, you need to work harder at keeping pressure off your thighs by using more upper body strength. Sometimes a gymnast will relax the upper body as the lower body rotates around the bar. This is not ideal mechanics. Like for instance, a back hip circle. You may feel your upper thighs and hips contact but the majority of your body weight should be supported by strong upper body strength and a strong grip. I wouldn't use lotion on your thighs to do bars. It will accumulate on the bar and cake it, making it slippery. Chalk is fine. Try doing casts in a row concentrating on having your body weight supported by your upper body. A good drill for gaining upper body and abdominal strength for bars is to do a handstand on a floor bar and have a spotter lower you to the bar (staying in a hollow, tight position) until your hips are on the bar. You will feel the muscles being used that are needed for strong bar work. I hope these suggestions are of some help.