What's the basis? the actual engine specs? because they still call 101 cc or 102 cc engines 100cc... and these engines already exceed 100cc...
Because of the number pi in circles, it is very hard to make an engine with a displacement of a round number.
I don't know how the law are in other countries, but here it would be illegal to ride a 101cc engine if your license is only up to 100cc.
The widespread law of max 50cc is also the reason why many scooters are 49.5cc
