Piki.
Over the years I have forgotten so much stuff and getting a 750 and joining this site my knowledge is returning in lumps.
After attending a Honda course in Chiswick London its all flooding back.If memory serves me right a full service for any four was four hours which I achieved in 2 hours and I did them right after they cooled down enough.
400/4S I could get them to go to the red line in top gear the speedo always said 110mph and I was no light weight.Once in my whole life albeit down hill I got my 750 off the clock and off the rev counter god knows how fast I was going but one of the blokes I worked with had a KO and he said 130 was obtainable with a Honda clock.I would never dream of trying to achieve this today but today she buzzed along at 80mph with no problem and wanted to go further.The key with these old Honda's as it was then is to keep them regular serviced and to take in all the short journeys you have done.Hope this helps
Cheers
Bitsa