I lubed my throttle cables and grip with Dri Slide (Bike Aid), and the throttle that once snapped back reasonably well when the steering was pointed forward, and snapped back poorly when it was turned to full lock now snaps back crisply in every position.

Dri Slide is definately worth the 10 bucks it costs (of course I kind of 'borrowed' it from my dad so it didn't cost me anything...yet).

Of course, I also make sure the rubber gel grips weren't touching *anything,* since that's where a lot of friction comes from. I had to cut a section off the throttle grip to make them the right length.