honda x8r 2002 not starting?

Hi all need help asap went to ride my scooter home from work and when i pulled the throttle it died and when i went to kick it over it wouldnt start at all. Checked the spark plug and fuel. Cleaned carb and changed vacuum pump underneath but still no joy. Was doin it for a while when i was riding it would drop in speed then pick back up. Now it has just died and i need it for work can anyone help please