Slow Riding takes a whole new meaning when combined with turning a heavy motorcycle.
For handling a heavy motorcycle at slow speed successfully, you need to use all the 3 controls in a coordinated fashion: clutch lever, rear brake pedal, accelerator (as needed). The below info graphic explains this:
Here are a couple of videos to give you an idea of heavy motorcycle handling:
1) How to pick up a heavy motorcycle
2) Police motorcycle training on Harley Davidson