Because everyone's age, driving record, location, credit rating, and special deductions (e.g. HOG membership, recent motorcycle safety course, etc,), all of which affect the premium price, are different I can only provide anecdotal information related to me because I just renewed my Harley-Davidson insurance through Progressive last week. The annual premium was $197 and that is about $150 less than getting the identical coverage through AmFam that covers my homeowners policy and the insurance on my four cars. I have no complaints at all with the Harley Davidson insurance through Progressive.
Always remember that for every mile of highway there are two miles of ditches.