I have both and also previously owned a 91. There is technical reason for performance variance from 91 - 96 but 96/97 are identical. Are the exhaust pipes identical? All I can imagine is a bike that has been better ´run-in´ and ultimately better maintained. Remember that clean, well-working carbs, good sparkplugs and an efficient airfilter can do wonders to individual bike performance. Regards and safe riding Andre