Had a similar problem with my 660. First thing I tried was to clean out the fuel filter. This helped but not alot (with the starting but ran smoother after it was started). I switched to premium fuel which made a difference ( a little on the starting but better after it was started. I then broke down and had a block heater installed. Still a little tough getting started when it is -20 but will start. The next item on my list was to change to the oil to a 0w30 (need to watch this as I have heard that you need a special type for the clutch)
Not sure if this will help or not. My dealer did tell me that they were tough to start in the cold.