Anything makes sense in Sports politics....
Traditionally Grand prix racing sizes were 50, 125, 250, 250 and 500. In the 60s, mainly as a result of restrictions on multiple cylinder engines and also because of some brilliant *East* German innovations in two stroke design four stroke engines disappeared from the GP scene.
These days its considered
1) unacceptable to have two strokes and
2) silly that the premium GP class has engines a fraction of the size of the lumbering monsters you guys have on the road.
So what's happening, *very roughly* speaking with *much over simplification* is that two strokes are being banned and engine capacities are being doubled, so what was the 125 class is getting a 250 engine, what was the 500 1 litre and so on.
yours with the 40 year old DS7 250 Yamaha in the garage...