Throttle cable assembly

[Howard]

My Agility 50 had a frozen throttle cable. I replaced the cable it now moves freely as it should. However there does not seem to be as much tension on the cable as it should so it does not always return to the idle position when the hand grip is released. It doesn't seem to stick, the least amount of pressure causes it to return to idle but it shouldn't need this added twist. I have sprayed the spring at the end of the cable (next to the carb) with penetrating oil and it doesn't seem to be stuck. It just needs a little more strength. Any ideas?
Thanks

[blue]

Had the same prolem befor I just  cut a piece of spring of to make it shorter and bend it back in place it makes the spring tighter.

[ScooterCommuter]

If you had enough corrosion in there to freeze the cable, I'd look for other "sticky spots" as well. Try disconnecting the grip from the cable and see if you can feel any binding at all there - it should move very freely. If the grip is binding at all it doesn't take much of that to overcome the spring at the other end of the cable. Tightening the return spring may just mask the problem instead of fixing it, and if you leave any corrosion in the grip it will only get worse.