ELI5, Why do some engines, even though they are the same size sound different. For example, a BMW s1000rr has the almost the same engine as a Kawasaki zx10r, but, they sound so different at idle.

Question

ELI5, Why do some engines, even though they are the same size sound different. For example, a BMW s1000rr has the almost the same engine as a Kawasaki zx10r, but, they sound so different at idle.

In: Engineering

Answer 1

There are many factors in how an engine sounds. Firing order and interval plays a big roll, bore and stroke differences, intake design and exhaust design. These all make a difference. An engine that fires cylinders 180 degrees apart will sound very different from one that fires 90 degrees apart.