Your new cable is fine just the way it is. It's designed to work just as it is with your stock lever and the lever 650central sells.
If you use a lever off a different bike it may need some adapting. My 75 has the lever off an 82 650 Seca and is a bit long. So I adapted my side cover to accept an adjuster like at the lever. I'll post a pic, This lets me take most of the excess slack out of the cable before I use the lever adjuster.
To adapt the side cover the hole is just the right size to thread to match an adjuster like on the lever. Just thread the cover, then slip an adjuster on the cable and insert the cable in the cover and thread the adjuster in. Oops almost forgot. The big round lock nut on the adjuster is to big to fit flat on the cover, need to put a regular nut on there. You will see that in the pic.
This mod will let you use a good, but stretched cable for a bit longer. That's why I did it at first, to make up for the stretch of an old cable. I wouldn't run the stretched cable very long, just long enough to get a new cable.
Leo