Before we start, it’s important to mention where we began.
Why do Safety Bikes have slacked headtube angles, riser handlebars and headset spacers?
To prevent a rider going over the handlebars in steep sections
Other then looking cool, this is why your current Safety Bike is setup that way.
Because Mullet frames have been optimally designed around a smaller rear and larger front wheel, the rider becomes tucked into the frame- As opposed to riding on top of the frame. This enables us to use an optimum head angle and BB height that aren’t capable on a Modern Safety Bike.
Mullet frames have been purposefully built around two different wheel sizes. You CANNOT setup your Mullet with the same size wheels front/rear.