When I lived in Germany in the 80's there were plenty of small singles and twins decked out as cafe' racers. Clip on bars, sticky tires, and not much else.
I wanted to replace the front foresail - I mean stock fender - as it's ugly, ineffective for street use, and catches gusts on the highway - especially from 18 wheelers.
I bought two fenders from Maier. the first is a superbike-style that I haven't tried yet. The other was a classic cafe'-style "coffin" style. Painted it with Grabber Green Duplicolor that is holding up very well so far.
This fender has quite a bit of clearance, so even if I picked up a thick coat of mud, I don't think there'd be a problem.
Other visible mods are larger front brake, large rear rack, barkbusters, Honda XR mirrors, new rear brake bracket. Planned changes are 16 tooth sprocket, better street tires and a 19" x 2.5" wide front rim with a 110/80x19 section. Progressive front springs, need to change the oil!