ulfg95,
So what your saying is I can run pump 87octane in my bikes, which are stock. I have no problem with that and it wil be much cheaper thna buying 92. But, here is the big one. My Scrambler DOES run much better on the 92 than the 87. And even then, I added Beryman's B-12 octane boost. It smells like paint thinner and eats paint just the same. It says it will raise octane up to 7 points. And with a very calibrated eyeball I dump some in my 5 gallon tank. It absolutely increases performance on both bikes. No, they do not do wild out of control wheelies, but there is a noticeable difference. Awesome advice from everybody. Polaris rules.
PD

 

If it isn't causing piston damage run it. I am just stating factual info. Higher octanes do burn cleaner. However, I burnt a 400 down from running 93 Octane. How do you know for sure it is running better? I'm not saying it isn't, but have you ran it through timing lights? That is the only way to be sure 100%. We clutched a Polaris 600 Edge X last year and it felt super fast until we ran it through the lights. Then we returned it to stock. Seat of the pants feel can give very very wrong readings. When you use timing lights while doing different mods you learn to basically never trust your seat of the pants feel. Any serious racer will tell you, "Yeah it feels faster, but is it." Ride in a 12 second manual tranny car then jump in a 11 second auto tranny car, without knowing the time I garauntee the manual tranny car feels faster. However in all reality the time slip doesn't lie. If it truly runs better, great, but 9 out of 10 my money is on the others.

 

Here's my two cents.

Before I did any engine mods to my 300 xpress, I tried each of the four grades of gas 87, 89, 93 and 103. I too, noticed a difference with each one. I wouldn't say better performance all around but in different areas. It seemed to me that the higher the octane the better my low end pulled but I think I lost rpms of my top. I don't have a tach to verify this but I believe it to be true. I have argued this with many engine builders and mechanics and still haven't completely resolved it. I believe(through my own experience) that the higher octane fuels actually slow my top end down because it is taking them to long to burn. My engine was all stock and didn't have the compression to burn the high octane fuels fast enough. I will also like to add that the 103 racing fuel made a hell of a difference when I would shoot up a gravel hill. This is how I measure my low end pull.

I have since then rebuilt my motor. I ported and polished and raised my compression(I still don't know how much, my gauge is broke). I know will only run 93 atleast until I see what my compression is. This has been the greatest increase in power out of all the mods I've done. I am still running the stock carb and pipe. I will change these later when I get some more $$$$$$.

 

polarisdood,

Judging by your signature, it doesn't look like you haven't done any serious engine work to either of your 4-wheelers. Knowing this, I really feel that I should tell you that running higher octane gas in a stock engine designed to burn 87, is going to give you almost NO horsepower boost at all. In fact, you may even lose horsepower.

The octane level of a fuel is a rating that judges how easily the gas will detonate. Gasoline is, for the most part, a combination of hydrocarbon chains. Octane, which is actually a hydrocarbon molecule with 8 carbons (hence, "oct&quot --which resists detonating very well, but is relatively rare-- and heptane (7 carbons) --which detonates very easily, but its extremely common-- are used to make up the combination in gasoline. So 87 octane gasoline is gas containing 87% octane, and roughly 13% heptane. The higher octane rating, the higher the compression must be in order for the gas to detonate (without a spark). If the stock engine will run fine with 87 octane gas, there's absolutely no need to buy the 93 octane, because there's no problem with it predetonating anyway. So, buying the more expensive gas is a waste of money, even though it may FEEL like you're going faster, you really aren't. It's entirely mental.

As for octane boosters... when they say that they boost octane 2 points, or whatever, what that ACTUALLY means is that its boosting your octane level 2 TENTHS of a percent! So a 2 point octane booster would take your 92 octane gas to 92.2 octane! That's a waste of money ON TOP of a waste of money!

Finally, aircraft fuel is just gasoline with tetraethyl lead added in (read: leaded gas). The tetraethyl lead additive does a wonderful job of boosting the octane rating of the gasoline, but for one, it contains lead, and lead causes lead poisoning, among other things. That's bad. And two, like I already said, the higher octane means nothing if you're running fine on 87.


[edit] I realized soon after I posted this message that most everything I said had already been stated by everyone else. Sorry for the repetition, everyone! [/edit]