You are right. Just got my cool bike yesterday,no dipstick. Did you find out how to check oil? I did find a Clymer Yamaha book, but it is for XS750 &850 Triples 1976-1981. (hold on a min.) OK, they refer to a level gauge furnished in the owner´s tool kit. Okay, found it. Engine oil level is checked by viewing the oil level window located on the lower right-hand side of the crankcase cover. Just looked, the SR 250 has a oil level window also. Now, this book recomends SAE 10w-30 for temperature 59 degrees F and lower, SAE 20w-40 for temperature 40 degrees F and higher. Good Luck, Jim