Describe loose?
Are you comfortable opening the right throttle switch first ? and see if there is any breaks or move the cable up a second notch inside the grip and try that?
Also the cable has an adjuster , adjust it with 2 spanners until you feel there is about 1-4mm pull before it bites the carb ?
Not unless previous owner fitted a cable that was too long for the bike. (Click “Add media” button when replying and insert a photo to this forum, so we can see it
or upload photo to a place like DropBox/OneDrive/Google Drive and post the “share link” to this forum)