I have a 2005 xb9r, I put some octane boost in the other day for the first time and I could tell an immediate difference. I have an open airbox mod and a D&D exhaust. I was thinking about 110 octane but I don't know if that's a good idea.

True "race fuel" is oxygenated to enable getting another couple of hp. High octane fuel without oxygenation additives slows the burn (resistance to detonation) and can cause one or two hp loss on stock bikes. Tests done several years back showed even using premium pump gas in a bone stock Hayabusa (they had pretty low compression - 11-1) could clip as much as 3 hp off the peak. For your Firebolt, using anything other than pump premium (unless actually racing) will be tossing your cash into a burn barrel.

Thanks Duane, would 98 octane unleaded pump gas help? I was going to get 110 octane 6 dollar gas. Thanks for saving me the money. Eric

Thanks Duane, would 98 octane unleaded pump gas help? I was going to get 110 octane 6 dollar gas. Thanks for saving me the money. Eric

I don't think you have enough compression to truly make use of more than pump 91/92. The higher octane ratings are to prevent detonation under high loads - such as high compression and does not actually add power - it merely burns just a touch slower to prevent engine damage. We don't have 98 around here that I know of. 98 octane might allow for a bit more aggressive timing with a programmable ignition, gaining 2-3 more hp. This might be good if you plan on racing. Race gas can be spendy and is not "magic" when it comes to power. However, if you were to run 13-1 compression, the 110 octane would be mandatory.

You see "pros" and "tuners" use race gas with oxygenated additives to pull maybe 5-7 more hp on a high compression, 150-200 hp engine. Shops like Lee's Performance stuff it in to show what the full potential is on an engine build, when going for broke on the dyno, when the engine will run fine on premium.

When I had my Hayabusa dyno'd I ran a 1/2 tank of 87 and 1/2 of 92 octane. 156 hp. I did not need the 92 octane but put some in as protection (mostly for my heart!) for the dyno pulls.

I did fill my 1200R with 92 octane for it's dyno run (72 hp), as I had done a stage 1 and was not sure of the A/F ratio. But, for 9,000 miles of street riding, it has seen only 87 octane.