i asked about the high altitude trx 250 honda about if it would run in colorado with just removing the air filter cover and got some great answers but would a higher octane gas in colorado comming from texas maybe help out in high altitude anyone with a clue i would sure apriciate your help and thx again for the other topic...

 

It will actually hurt.
O2 speeds up the burn rate. The higher up you go the less O2 you have.

In other words, if you were right on the edge of detonation lets say in Colorado and go to lets say the LA dunes, your engine will detonate because your engine will get a bigger gulp of air on each piston stroke.

 

Higher octane at higher altitude will help with pre-det or knocking and can prevent burn down especially on two stroke machines if jetted a little lean. I always run higher octane fuels in my snowmobiles because of changing elevations and the lean jetting I run. When riding in the mountains, I jet for the highest elevation I will be running, but you never start out at the elevation.
Ex: I ride at over 11,000 ft., but start at 7000 ft. So buy using a higher octane fuel, you prevent any pre-det at the lower starting elevation. However 4-strokes are a little more forgiving.
Just remember: Higher octane fuels DO NOT produce horse-power, only prevent and prtect against pre-det.

 

I live in Co. and use higher octane gas but not for the reason you would think, it is because regular unleaded gas is only 85 oct!

 

While you are in Colorado, notice that pump gas has a lower octane than down at low altitude. Decide what that is telling you......