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The MAIN reason is having quality gas. We all spend so much time and money building and maintining our bikes with high end parts and meticulous labor. Why risk dirty ethonal dilluted pump gas in it? The gas pumps around me have sediment in them. Find it in new gas cans and in my mower gas tank. No bueno.
Was it hiding in a SAFE space or what? Remind me not to make my bike angry. I hope it doesn't decide to stop running on race gas while your on the track
Gasoline is the most misunderstood and overly scrutinized piece of the combustion process that I have ever read.
Race gas does not matter if you don't have the compression to support it. It's a slower, longer burning fuel that will make less power all things being the same.
My stock KX450 calls for a MINIMUM of 90 with the stock CR over 12:1 which can easily handle more than 90 octane. I think once you go crazy to like C12 is when you see diminishing returns on the power... but what the hell do I know I just want consistency and I like the smell of C12 in my TMR built KX250 and the Sunoco smells pretty good in the 450 too!!!!
Octane and burn speed are not the same thing.
That is true with all things being equal. But the race gas will allow you to push your timing further than pump gas will and tune it more aggressively. That is where the benefit and added power comes in. But if you are just going to dump it in and expect it to make more power, it will not. In fact, if your engine was already jetted or mapped perfectly, adding race gas can make less power. If you dump a good quality oxygenated fuel in a stock bike that was maybe mapped a bit rich, it is conceivable that you would feel a bump on the butt dyno.
My buddy had a banshee drag couch that was ported for 100 octane. He tried running some 112 in it and it lost a big amount of power. The pipes got so hot they started to bubble the plating off.
Pit Row
Moving to 40 degrees BTDC doesn't yield any power gain, and beats the shit out of the main and rod bearings in comparison. Dropping to 34, power falls off.. moving past 42 the plugs start to glow red and the Motor will start popping.
Moving past 22 degrees of INITIAL timing leaves you a car that won't crank over and start.
Your timing is all in by 2200rpm, so what's the difference? We would run AvGas or C12 and nothing would change, except a loss of peak power.
If your dirt bike has 12:1 compression, and combustion chamber design likes "X" amount of advance, if the octane contents supports it, race gas won't help. Yes, if you upping the compression, it's a hot day, your lean, and running a long moto i would agree race gas in necessary. It is not the FUEL that's giving you the power, it's the mods you did. The fuel just gives you the ability to avoid detonation.
Now, if you want to run nitro methane, or alcohol that's something different. Anything that cools intake charge, or creates oxygen (like nitro methane does) your starting to have fun.
I don't think adding a little race fuel to your bike will hurt, maybe safe if you don't clean your radiators or it's extremely hot out. I just wouldn't go spend 10$ a gallon unless your trying to run a pro national.. of course, maybe you want to. I'm just being logical.. work on your corner speed
Sunoco and VP wants you to buy fuel. It's good fuel.. I'm not denying that.
I understand sometimes a higher octane fuel is slower burning but it is not directly caused by octane. You said it is a slower burning fuel, that is not true in many cases. Sunoco Supreme is one of their fastest burning fuels(much faster than pump gas) and has 112 octane.
Detonation is an explosion, the ignition process is a controlled burn. Octane is the measurement of the ability to resist detonation. The speed of the ignition process is determined by the hydrocarbon makeup of the fuel. They are entirely separate
Beside that, here you can leave pump gas for 6 months sitting in the carb, and no gum is going to form neither it is going to rust anything.
I hope your burn rate is long enough to chase the piston to the bottom. Good luck, I would buy the MOST expensive fuel you can find. It will make the difference, now everyone is happy.
Good day.
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