It has nothing to do with the exposed engine. 99% of the sound comes from the exhaust, which is built do be quiet (destructive interference) or loud (constructi

It has nothing to do with the exposed engine. 99% of the sound comes from the exhaust, which is built do be quiet (destructive interference) or loud (constructive) of exit gases. There are 300 hp cars that are quieter than 50hp motorcycles because of that