ok im not new to the motorcycle thing i have quite a few actually, but i am smart enough to know high compression motors need high octane fuels. I am currently looking at an 08 yz450f i know the guy who owns the bike. It has a rough idle and has had 87 ran through the gas tank its whole life which is an estimated 20 hours. i heard this could scar the cylinder. Just wondering what some of the other side effects could be?