I've had my "09 900 Classic since April 20, 2010. I bought the bike new it has 1400 miles on it. I was using 91 octane fuel for a while. But recently I switched gas stations. The new place I go does not offer 91 octane, they have 93 octane. Since switching, I've noticed a throttle body backfire that happens on quick throttle input (feels like the air cleaner is gonna blow off!!!). Dealer had nothing. Does anybody else have this. Is it just the higher octane....or something else? Just wondering.