I flew the Comet 4B with BEA (now BA shorthaul) in the 1960s so my memory is struggling but I am fairly sure the nosewheel was raised at 80 kts to 'skim' the runway in order to reduce the vibration from an out of balance nose wheel.
The nose gear leg was relatively slender and some shake could often occur in the flightdeck on getting airborne so raising the nosewheel off the runway at relatively low speed kept it to a minimum.
The 4B was a completely different animal to the original 1s, with different engines and longer fuselage. The leading edge of the wing may also have been different. It had a number of traps for the unwary, not least being Mach tuck at .83 which was horribly close to the cruise speed of .79. It could often reach coffin corner too. We used it into Berlin Templehof one winter and I think we could manage a respectable 330kts in the corridors.