Explain the terms of a 66/80?

[jman116]

I understand what the CC rating of an engine does, it's the displacement, but why do some list it as 66/80 rather than something like 66cc? Is it a ratio, or does it mean it can convert between the two?

 

[Jag]

I understand what the CC rating of an engine does, it's the displacement, but why do some list it as 66/80 rather than something like 66cc? Is it a ratio?

80 is what they measure in China, to new people it makes the engines sound like a larger displacement, it is actually a 66cc engine

 

[jman116]

80 is what they measure in China, to new people it makes the engines sound like a larger displacement, it is actually a 66cc engine

Thanks!