Need help really high revs on start

I need help i bought a scooter not long ago it ran ok for a day and then the air filter fell off it, so i got a new air filter but the bike jumps to 8500rpm straight away ad i have to turn it off can any one help me i dont know what to do, is it sucking in too much air? is the carb broke?

 

So i guess the fuel to air ratio is incorrect, my carb is also old

 

Check your idle screw isn't wound all the way in or your throttle cable could be slightly too short or routed wrong.

 

Thanks iggy it was to do with the idle screw just need to get the fuel to air ratio