The older Royal Enfield Bullet motorcycles, particularly those with the cast-iron engine design, are known for their relatively high top speeds compared to their power output. There are a few factors that contribute to this characteristic:
Engine Design: The Bullet's older engines, specifically the cast-iron engine design, have a long stroke and a relatively low RPM limit. This design favors torque production over high-revving power. The long-stroke design allows for good low-end torque and helps maintain a steady power delivery at higher speeds.
Weight and Aerodynamics: The Royal Enfield Bullet is a heavy motorcycle, and its design prioritizes stability and durability over aerodynamics. The weight helps provide stability, while the upright riding position and the large frontal area create some drag. However, at higher speeds, the weight can aid in maintaining stability and the drag forces become less significant, allowing the bike to reach higher speeds.
Gear Ratios: The older Bullet models typically have a long and tall gear ratio setup. This means that the final drive ratio, along with the gear ratios in each gear, are designed to allow the bike to maintain higher speeds without reaching the engine's maximum RPM. The tall gear ratios help the motorcycle achieve higher top speeds despite not having a high-revving engine.
It's important to note that while the older Royal Enfield Bullets may have a relatively high top speed, their acceleration and overall performance might not be as impressive compared to modern motorcycles with more advanced engine technology. Additionally, modifications, maintenance, and riding conditions can also affect the top speed and overall performance of any motorcycle.