Hi, I have an 81 BMW R100RS that was given to me and I do not know much about bikes. I´m going to list and sell it, however upon checking the odometer reading, it reads 02670. I know it has at least 60,000 miles from looking at pictures taken of the bike a while ago. So, my question is: What would account for the zero in the start of the mileage? Is that the odometer rolling back or? Please excuse my ignorance the subject. Any help would be much appreciated. Thank you.