Motorcycle Gap Insurance Regarding To Motorcycle Insurance?

Regarding to Motorcycle insurance? - motorcycle gap insurance

Hello,
I am 24 years old, male. My plan is to provide the Yamaha R6-I'll Be funding cycle.
I have some questions about motorcycle insurance.
My friend has a Suzuki GSXR750 06, was his first motorcycle, and is a new bike. However, the coverage is only $ 120/month.
Searching online (GEICO, Progressive, Allstate), I learn that all of the coverage available on the bike $ 487/month-which strange. Because I am older than my friend, he was 22 years.
I understand that you need a full coverage (collision, comprehensive coverage fund), if a bicycle. My friend is also the financing of the bicycle. But how is their coverage of the cheapest way I wanted it?
I also took the $ 500 deductible on comprehensive and collision as well. However, it was the lowest I that no one 487/month-if $ $ 880/month.
Unless the decline in Comp and Coll is my cover only $ 84 per month. Why is there a big gap in my reporting from my young friend, to a larger cc bike? 600 vs. 750th