I have a throttle and idle cable I got from the dealer, one has a connection for a sensor; the other does not. My old cables do not have this connection. Is this the wrong throttle cable?

Also, does anyone use JUST the throttle cable? Is the idle cable necessary?

Gracias in advance!

 

OK, I guess the sensor connection is for cruise control.
And two cables is recommended for safety... correct?

 

You are correct with both answers.

 

The idle cable pulls the throttle back to idle when you let go of the throttle - "which is nice".

 

Well not really. The bell crank spring on the carb / throttle body closes the throttle and pulls the throttle cable "back." The idle cable is a government mandate to work if the carb/throttle body ever sticks open. ( Useless IMO.)

To the OP, the one with the switch is the idle cable for a bike with cruise control on a Touring bike, and if you don't have cruise, then you paid extra for it too.