State Farm (who I also have home and auto) once told me "we only insure bikes because you have other policies, and the rates are primarily tied to engine size." Which means a 1200cc cruiser was the same as a Hayabusa, or an FJR. All of which are ridden in different ways mostly by people with different ideas of riding.
This is not the case any more. Now, they use crash statistics like the big boys. They used to have good rates, esp. for fast, small displacement bikes. Not so much any more.
At one point, they tripled my rate for no reason I could tell, and I dropped them like a hot potato. They're still competitive for cars, but not bikes.
First wanted to point out something went wrong with that quoting of the prior post, that was something I wrote not Patmo.
Second, I've not noticed any great increase in my MC insurance rates from State Farm, certainly not anything even close to a 50% increase, let alone triple the rates. So its not likely a corporate wide change. (Trust me I don't stay with any company that has that kind of increase.)
Insurance is one of those things that just cannot be easily compared, unless you live in the same area with the same history, etc.