you should still check it every ride to make sure it isn't low and that it is still the correct color.
"Next, check for fluid oxidation. The sniff test is a good one, but a "blotter test' is even better. Put a few drops of ATF on a clean paper towel. Wait 30 seconds, then examine the spot. If the fluid has spread out and is pink, red or even light brown in color, the fluid is in satisfactory condition. But if the spot hasn't spread out and is dark brown in color, the ATF is oxidized and should be changed."