Love these prints. This batch is for my daughter, I'm going to make another for me.

I printed the hard tyres (white) with a regular Z-axis change which created a seam down the back. So I tried a random Z-axis change on the soft (red) and medium (yellow) tyres, which caused the surface of the tyres to be quite pitted. My wife says they just look like they've had a couple of laps. I went back to the regular Z-axis change for the inters (green) and wets (blue).

Needing to conduct a filament change for the colour change on my Ender-3, after the change on the hard tyres, the nozzle started to print at the "P Zero", which didn't take immediatly well. So for the other stacks I rotated the model before slicing so the nozzle would start the new colour on one of the solid lines. This produced a much better finish.

0.2 mm layer height
200C
60 mm/s

between 2.5 and 6.5 hours printing per stack.