The maximum-but-comfortable speed when riding a motorcycle can vary depending on various factors, including personal preference, road conditions, weather conditions, and local speed limits.
The Kawasaki Z900 RS is a powerful motorcycle known for its performance capabilities. It has a top speed of around 225 km/h (140 mph). However, riding at this maximum speed for a prolonged period on a 500 km highway may not be comfortable or advisable.
When riding on a long-distance journey, it's essential to consider factors such as fatigue, fuel efficiency, and safety. Maintaining a constant high speed for an extended period can be tiring and may reduce your concentration level. Additionally, higher speeds often result in reduced fuel efficiency, requiring more frequent refueling stops.
As for a comfortable cruising speed, many riders find that traveling at speeds between 100 km/h (62 mph) and 130 km/h (80 mph) provides a good balance of speed and comfort on long highway trips. It allows you to cover the distance efficiently while still maintaining control over the motorcycle and being aware of your surroundings.
Remember to always follow local traffic laws and regulations, adhere to speed limits, and adjust your riding speed according to road and weather conditions.