When I did my 15K service I noticed my primary oil was almost dirtier than my engine oil. I assume this is from clutch wear but wonder if Im maybe riding the clutch on take off causing this to occur. Smelled awful. Measured what drained out and it was almost exactly 1 quart. Ive been using HD SE Syn3 since 1K service.

 

Normal. Syn3 is fine as it contains no moly. But I would change it at 5,000-10,000 vs 15k. My primary oil gets dirty at 5,000.

 

Im sorry,I didnt add the fact that it has been changed every 5K. I wouldnt dare let it run longer. Oils too cheap to skimp on. My ride has been serviced religiously at 1K, 5K,10K and 15K. Funny, I asked a few friends that have owned HD's longer than I have and got several different trains of thought on service intervals. One changes oil(syn) at 2500 miles, I change every 5K like the book says. Another changes engine oil at every 5K but does his primary and trans once a year BUT he doesnt ride as much as I do. I may adjust my primary change to a shorter interval so it stays clean and maybe the clutch will last longer. The trans oil in mine at 5K(Syn3) was as clean as the day it was put in. Thoughts on this?