Hello. I am considering buying a 1997 GN125 This bike is in mint condition, I mean Perfect! It has lots of chrome, low miles 3,400 miles (the seat has not even been broken in yet! I was wondering what is a fair price for this bike? Also wondering top speed? I am 6ยด3 245 lbs. Kinda concerned that bike may not have the power to carry my size... Any comments would be greatly appreciated! Also I saw something about a performance chip? Is tha for real??