Check the rear brake lever feel on another Silverwing.
When I rebuilt our orphan Reflex the spongy feeling of the rear lever after bleeding drove me nuts until I compared the feel to the Silverwing. I arrived at the conclusion that the lever needs enough travel to trip the start relay micro switch.
The first click you here is the brake light switch; the lever should feel somewhat spongy until you hear the second click. If the lever firms after that click is heard, you should be good to go.