I went for a ride yesterday and prior to starting the bike, I pulled the choke out ('04 Vulcan Classic Carb'd) and I noticed the choke knob slowly slides back. If I physically hold it all the way out the bike fires right up. If I just pull the knob out (and release it) the bike hesitates to start because the choke knob is sliding closed. What is the simplest way to fix this problem? Do I need to replace the choke cable? Any input would be great, since it is winter it is time to do these little maintenance things.