Well, having made the jump from a zxr250 to a zx7rr (which has about the same power as a modern IL4 600 ccm sportsbike but more weight) just yesterday I think I would put it this way:
If you possess a healthy amount of discipline and a strong sense of self-preservation you MAY be ok.
Without at least those two you're likely to get into trouble very very quickly
As MSTRS said, a modern 600 ccms would most likely have all the go you could possibly want coming from a 250. It's a completely different ballgames.
It is preferential to refrain from the utilisation of grandiose verbiage in the circumstance that your intellectualisation can be expressed using comparatively simplistic lexicological entities. (...such as the word fuck.)
Remember your humanity, and forget the rest. - Joseph Rotblat
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