The Evaluation Method of Surge on Motorcycles
We studied the mechanism of occurrence and evaluation of the surge that is produced in motorcycles equipped with 2-stroke cycle engines by simultaneously measuring chassis behavior and combustion. When modal analysis was performed by measuring the acceleration of each chassis component while placing the test vehicle on a chassis dynamo, it was found that pitching, in which the tires serve as springs, and resonance, generated from the rear suspension spring, occurred simultaneously during surge generation. The major component that is felt physically is pitching. Although a certain degree of correlation was observed between fluctuations in combustion and occurrence of pitching, since the drive line contains a large amount of back lash, the system has a high degree of non-linearity, thus making it difficult to obtain a well-defined correlation.