accountantpete
OAP
I see now - what I didn't appreciate is that Cannondale have fiddled with the bearings so as to enable a greater amount of outer angle - so that the bearing sits 2mm higher in the headtube - hence the gap.
As I see it you have four options:
1) Use the bearing as is with the gap - there is less contact area between the cup race and bearing so it is not ideal but may work ok. Also see if a different crown race can be fitted which lowers the bearing a tad.
2) Get a similar bearing but 5/6mm deep instead of 7mm - this reduces the gap but you still have the reduced contact area.
3) Get the Cannondale headset
or
4) Get another internal headset that fits the bike.
As I see it you have four options:
1) Use the bearing as is with the gap - there is less contact area between the cup race and bearing so it is not ideal but may work ok. Also see if a different crown race can be fitted which lowers the bearing a tad.
2) Get a similar bearing but 5/6mm deep instead of 7mm - this reduces the gap but you still have the reduced contact area.
3) Get the Cannondale headset
or
4) Get another internal headset that fits the bike.