I bought my 1998 CBR 1100 used with 15,000 km on it and rode it an additional 10,000 km this year. Riding 2300 km one weekend was painful on the wrist so I added helibars. To allow rides of 12-16 hour days I will also be adding foam to the seat and lowering the front footpegs. The bike was designed for those under 5 ยด 10" tall so adjustments are needed for extended riding. I rode an 1984 Honda V-65 Sabre before this bike which was more comfortable on long days in the saddle. If you ride only 4-6 hours a day none of these adjustments are necessary, in my opinion. I will also be adding an auxiliary tank of 15 litres by cutting the stock seat in half and mounting the cylindrical tank complete with a backrest behind the drivers seat. This should give me about 450 km range between refueling.
The bike was a bit high geared for my liking so I changed the front sprocket to two fewer teeth which reduced top speed by about 10%. The acceleration has improved, the rear tyre wears out faster and the lower top speed is not much of a problem around town or on the highway.