As part of the annual maintenance, I replaced clutch and brake fluid on Saturday. Clutch fluid was totally dark brown after 12 months/5000 miles and so did the rear brake fluid. For some reasons, the front brake fluid wasn't as bad as the rear. After the fluid change, the rear brake feeling didn't change much. The front brake lever feels tighter. The biggest improvement was the clutch. Changing gears is much crispier now. I was actually surprised by the difference. I used Maxima DOT4 fluid for all. If anyone is riding with the OEM fluid after 12 months, I strongly recommend to replace both clutch/brake fluid with new one.