95 octane fuel for knock/rattle on 99 yz250

[jentzschman]

So, looking through the FSM for my 99 yz250 it says to use 95 or plus ocatane fuel. I have never notice a station that has 95.

After running the bike the other day I could hear a pretty audible knock/rattle that seemed to be coming in the area of the power valve.

After doing some research it seems one of two things: 1: its normal on these bikes... and 2: It's detonation.

The responses I read about it possible being detonation suggested to use higher rated octane gas.

So I figured why not give it a try and that leads to my question about where to find octane rated gas that high in the SL valley.

PS. What octane is pure gas and is that any better over ethanol based gas?

Thanks.

 

[Deleted member 12904]

91 should be fine at this altitude. My old 99 yz250 ran just fine on 91 and didn't even foul a plug in years.

 

[jentzschman]

Cool, good to know. Thanks.

 

[anderson750]

You won't find 95 octane at this altitude. If you need higher than 91 you will have to get it by mixing something like VP with pump gas.

 

[YOUKNOW]

You won't find 95 octane at this altitude. If you need higher than 91 you will have to get it by mixing something like VP with pump gas.

BOO-YEA X2

 

[glockman]

Harts in AF sells 100 octane as does one station on main st in Spanish fork. You can also try some octane boost in a bottle. I add it to my fuel station in my trailer if the gas has been in it for a while and it really helps backfiring in my 4t.


Sent from my iPhone using Tapatalk