It's bikes like this which i think an undertail exhaust would work very well and do a good job at cleaning up it's side profile:

unlike old cars, its much easier to keep and old bike, plus it all depends on how well someone takes care of itits amazing how well condition some of these vintage bikes are kept.
There is just less painted areas to keep clean but the biggest issues with older bikes are maintaining the engines.unlike old cars, its much easier to keep and old bike, plus it all depends on how well someone takes care of it