Just bought a 1978 XLCH Sportster 1200, it has been sitting for 10 years, the guy I bought it from said I should throw some Mystery Oil on pistons before starting.Anyone heard of this Mystery Oil? Where can I find it? What other oils will do this? How do you perform a compression check? I know I will need tune up and fluid change. Any other suggestions? Paid $1000.00 for this Bike.