Since the HD air cooled twin is a dry sump engine, the crankcase is very seldom ever drained. When it is, it is usually because of some problem such as a faulty check valve causing the case to fill with oil. If the oil was clean in the oil tank and the filter was replaced, they did their job correctly.

By the way, the aluminum alloy the crankcase and side cover are made of will stain the oil black in short order, so oil color alone is not a good indicator of oil freshness.

 

Save your money and your blood pressure. Get service manual on your bike and do it by the book and you will be surprised how easy it is to do these things yourself with a little wrench time not only will you be satisfied with the quality of the work but also the peace of mind knowing everything you wanted done got done . Especially since your a Wrench anyhow . And next time tell them to keep there warranty you just bought the dealer a free lunch .