New cars drastically drop in price as soon as the drive off the lot, so motorcycles shouldn't be any different.
650miles is far from a test ride. I'd say $3 but no less than $2 per mile discount with full warranty and any extentions if offered.
Also if your pre-approved for the loan on the bike, bring the paperwork, it will make haggling that much easier if they now they can make the sale that day, I brought in $10.5k cash, it was the easiest purchase that I've ever done.
Mine had 4 miles on the clock when I bought it. I know who rode it and why. (The owner of the dealership, testing after assembly.) I picked it up for $9900 (its an '07 not a Gen II).