Thanks for the replies guys.

I do not have access the build manual atm but all the aircraft paperwork suggests that the forward C of G limit is 11.37", apart from the permit to fly!

The permit states the range is 11.0 to 16.0" aft of datum with MAUW of 1400lbs (Rotax 912 ULS fitted).

However, I note from the aircraft log book that it was orginally built to allow operation up to 1550lbs and to take a Rotec R2800 engine so not sure if a forward sweep will have been incorporated. What is the easiest way to tell?

Also do not know the Kitfox serial number offhand but can check- if it is still on the little triangular metal plate behind the seats.