What kind of bike? Something's wrong with it.
You don't just "start your bike one day" and find out it's loud as hell.
Is the muffler loose? near the head?
Did you backfire recently? perhaps blowing out the wadding?
I know lots of people WANT to make their mopeds louder. But if it just started 'out of the blue' with no other symptoms or warnings.... something is going wrong.
If you're okay with the noise that's cool. but I would be concerned with tracking down the "why" it's suddenly 3 times louder.
Check the obvious nuts and blots...post the scooter brand/model so other owners can help.
Good luck!
Wayne