I prefer a light gray or flat white back drop. I find the black to be too dark and hurts contrast for the lines on the bike. Indirect lighting, no direct flash from the speedlights. 2 500W work lights, and a bounce flash is enough to start. Bokeh is good, but I think your aperture is too large as the depth of view is shallow in some shots and the bokeh too harsh. IMHO, bokeh is best with a detailed background, not monochromatic white or black.
There are a bunch of great photographers here who will soon contribute far more useful advice than I could.