Gt500 quicksilver rotax 582 rpm advance failure

I have a quicksilver gt500 with a rotax 582 

I have recently bought this aircraft and no little about them however found this issue on the first test run. 

Basically I can start the motor easily each time and raise the rpm to 2000 rpm however that is it. I get marginally perhaps an extra 200 rpm with the electric fuel pump turned on. I have gone over all the fuel lines and have replaced them and checked for air leaks I have also replaced the vacuum fuel pump.  I have cleaned both carbs and examined there simultaneous movements 

There is substantial fuel in both of the bing 54 carb bowls 

Any pointers where to look next would be greatly appreciated