Why isnt my rs as quick as others?

[croftie]

if you by them second hand then people might claim there full power when there not

mines got the fullpower engine in it though, with powervavle blade and that full functioning?
EDIT: Also my air filter doesnt have the 'snorkel' on it so i was told when i got it dyno jetted, would adding a race air filter increase its performance? on a 50 that was part of the de restriction is it the same thing?

EDIT:
so i have just realised why its not very quick, just looked at my dyno sheet for the first time. My supposed 'full power' bike is only running 22bhp! What the hell? Its got a 28 mm carb, and the engine has a working powervalve? Restricted models dont have a powervavle slot for it to go in on the engine? What on earth is my bike???