Octane boost?
Octane boost?
Does anyone carry octane boost for trips. I was just thinking about how I hate fueling on trips where I can't get decent gas. Does anyone carry any octane boost or anything for that problem?
Extreme HDF Member
Joined: Sep 2006
Posts: 10,033
Likes: 29
Octane boost doesn't work like most people think. If the bottle says it will raise your rating 5 points, that doesn't mean 87 will be 92 after adding the octane boost. Your octane will be 87.5....In a nutshell octane boost is a waste of money.....In me experience a HD will run just fine on 87, unless you have modded it and raised the compression.
I was just looking for some kind of additive to use on long trips where I can't always choose the fuel quality. I don't plan on using it for every tank, only those where I end up using cheap gas.
Ultimate HDF Member
Joined: Feb 2007
Posts: 7,663
Likes: 7
From: Northeast Ohio
Properly tuned, you don't need it. Hell, I was running 87 octane out west in my 120. Would I use it regularly - no, but I just altered by riding style (shifting later, running in a lower gear, etc) and it was just fine.
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Road Warrior
Joined: May 2006
Posts: 1,479
Likes: 4
From: SoCal
A 33oz MSR fuel bottle or two in your saddlebags will allow raising your octane rating when you're stuck filling up on 87 in the backcountry. Toluene or Xylene in these bottles from a paint store or chemical supply house will provide the same industry-chosen octane booster for your ride. It's true that regular use of high-octane fuel ratios will compromise your 02 sensors and this is why the octane sold in stores uses other solvents, and works poorly because as stated above it only raises your octane rating .03 - .05 percent or 3-5 "points. With a 5.5 gallon gas tank, 10% Toluene will get your about 3.0 more octane rating, 20% 4.2 more octane rating, and 30% about 4.6 more rating. Figure that 10% of your 5.5 gallon tank is 0.55 gallons, .55 X 128 = 70.4 oz. of toluene then fill up with gasoline. That would be 2 quarts of toluene (1/2 gallon) and 6.4 more oz.
Last edited by Firetender; Aug 17, 2009 at 01:49 PM.
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A 33oz MSR fuel bottle or two in your saddlebags will allow raising your octane rating when you're stuck filling up on 87 in the backcountry. Toluene or Xylene in these bottles from a paint store or chemical supply house will provide the same industry-chosen octane booster for your ride. It's true that regular use of high-octane fuel ratios will compromise your 02 sensors and this is why the octane sold in stores uses other solvents, and works poorly because as stated above it only raises your octane rating .03 - .05 percent or 3-5 "points. With a 5.5 gallon gas tank, 10% Toluene will get your about 3.0 more octane rating, 20% 4.2 more octane rating, and 30% about 4.6 more rating. Figure that 10% of your 5.5 gallon tank is 0.55 gallons, .55 X 128 = 70.4 oz. of toluene then fill up with gasoline. That would be 2 quarts of toluene (1/2 gallon) and 6.4 more oz.
Thanks for all the input.
