I have an F2 built in 1978. Engine No. CB750E - 2615478 Frame No. CB750G - 1015207. I believe that this machine is the same as the US 77 F2 model. Yes, mine does have the long filter bolt and the finned spacer block. The carburettors have the accelerator pumps and the needle height is adjustable - I think that on the 78 models the needle height is not adjustable.Hope this is of some help. Pat from Aust.