I'm running an inline regulator set to 2.5psi Rob, as can be seen in the picture. The SU's are being a pain to setup. I am trying to get the fuel height at the jet the same for both carbs but as the front float is made to being lower in the bowl than the rear, this is proving pretty much impossible. Does anyone know the actual reason why the float heights are 4mm different front to back? I've read a lot about it but cant find what I consider to be a valid reason. and if it is valid then why did they change to the same height front on later carbs?