I went from 87 to 89 since I had the stall to see if it would help. Then back to 87. I can't say the higher octane made any difference in the stall or performance. Gas falls into the same category as oil, unfortunately with all sorts of unsubstantiated claims about one product being different or better than another. The 10 or 20 cent difference between 87 and 89 octane price isn't that significant. I mean the price of all gas goes up and down by that much quite often. But I know a few people who burn regular gas in machines that ask for high octane and they also swear the car/bike runs fine. If you buy a performance bike and the dealer fills it up for you, most likely he put regular unleaded 87 octane fuel in it even if it calls for 93 octane.