a M-B.c bicycle? if that was my choice to make, i would opt for a one-off classic theme & this is what i would build:
take a classic 26" cruiser frame & put a traditional briggs & stratton 5hp minibike engine right where it belongs. rake it, triple-tree springer. cruiser bars with a >windshield<
worksman clinchers, single speed freewheel, drum brakes. big round blackwalls stuffed under full-skirt fenders. full chainguards both sides. sink a big ole cop's saddle in there somewhere. split the exhaust into two pipes, then twist them around each other in a straight line all the way back, down low, rejoin 'em for a single turndown.
a fully functional "it'll run forever" build...a tank, just an old chopped and channeled plymouth on two wheels. paint it deep purple, i think, with gray smoky flames just under the surface and barely visible light blue waves under the smoke.
wow. that was fun, i had to keep editing & editing... 8)