OK,if youre talking car youre in the wrong section but try WD40 anyway!! Firstly spray some WD40 into the twistgrip body where your throttle cable exits on the r/h handlebar,also try & get some down the cable by loosening the cable adjuster & pulling the outer sheath away, you should see enough to squirt some WD in. If no joy after all that, check that your cable isnt frayed anywhere, a little dismantling is called for here but is simple enough, if youve gone this far you could take the carb top cap off & check the slide for a totally smoothe operation.Good luck.
Chris P.Duck
January 2010