iv sorted the bike out noe i took the carb back of and stripped it and found i small pipe blocked that leads ito the side casing of the engine it now starts first kick and runs fine 
thanks everyone for your help 
im gonna get a years mot on it then it will be up for sale if anyones intrested its a aprilia rx50 x reg 2001 2700 miles 
good condition few minor scratches
£600
my email is shaunhall21 at hotmail.com
                
 shaun
                
 August 2010