Rode a xl 500 today and thought it had a fair bit of go , anyway i was wondering if i was going to buy one for trail riding would i be better of getting an older xr or xl. I have heard that the old xr's had problems with the cams and valve train wearing , is this true. Also do the xr and xl 600's ( 80-85 models) have basically the same engines. If they have the same engines would i be better getting an xr because it is more off road orientated.