I run the road bike tyres at 110 psi rear and 100 front, so will bump the rear Kojak up to 100 and see how that goes. The road I'm going on today has a generally good surface, so bumps shouldn't be a problem.

Incidentally, I wore out a Marathon tyre running it at too low a pressure, plus nearly skidded off the road when cornering on the road bike for the same reason, so learnt the lesson and keep pressures at the midpoint or higher of manufacturers' recommendations.