Regarding to Motorcycle insurance?

[dj_c5]

Hi,
I'm 24, male. I plan on getting the Yamaha R6-I'll be financing the bike.
I have some questions regarding to insurance of the bike.
My friend owns a 06 Suzuki GSXR750, it was his first bike, and he is a fresh bike rider also. But his full coverage is only $120/month.
While searching online (geico, Progressive, allstate), I find out that the full coverage for the bike itself is $487/month-which I found strange. Because I'm older than my friend, he's 22.
I understand that you need full coverage(collision, comprehensive coverage) when you're financing a bike. My friend is also financing the bike. But how come his full coverage is way cheaper than what I've searched for?
I also picked the $500 deductible on Comprehensive and Collision too. But the lowest I got was $487/month-if not $880/month.
When I decline the Comp and Coll, my coverage is only $84/month. Why is there a big gap for my full coverage comparing to my younger friend with a bigger cc bike? 600 vs. 750.