I got a bunch of quotes recently on several bikes I was looking at and it was interesting to see the results. Typical jumps for bikes over 500cc and then again over 750cc (although typically the jump came later for cruisers).
What I thought really interesting was the premium placed on certain brands. A Ducati with a bit less ccs than my Kawasaki 1000 had rated about 30% higher. Both bikes have essentially the same tested hp, acceleration, stopping distances, weight, etc… I wasn’t getting comp, so theft doesn’t factor. Turns out the premium is because the typical Ducati rider is more likely to wreck than the typical Kawi rider — so the Duc costs more to insure.