2 Stroke Oils' Effect On Octane

[bleedngreen]

Ányone out there know if different 2 stroke oils have any known effect on octane rating? After getting my head machined by RB (for pump gas), under some circumstances i.e.; sea level, steady cruise around 55 mph, I'd get a bit of pinging. Wouldn't happen over 1000' elevation.

Anyways, yesterday, I had been running Mobil 93 octane with Golden Spectro 52:1, oops, forgot my gas can, had to use my buddy's mix of Mobil 93 with Amsoil @50:1. Same gas, different oil--pinging's almost gone!

What gives? Tried searching on the subject to no avail.

Dave

 

[KDXRyder200]

Lets just say........

Amsoil is prolly one of the most expensive oils out there but its also the best.....i use it in my 89 KDX200 which has a number of modifications but i mix it at 32:1 so i don't fry the motor because i'm always on the pipe........ :laugh:

 

[levert]

I would think if there is an octane booster in your oil it would say so,it definitely would be more expensive.Oil would not change your octane level, you probably have a bike that is right on the edge and the second day with your buddies fuel and oil mix and different atmosphere conditions changed the point at which it pings.
Gas, even from the same mfg varies widely.I know around me that they mix different levels of ethanol in the gas, you never know if your getting 10% the max or zero.Although these mfgs say you are getting X amount of octane I would think a high comp motor could on any day with diff fuel and conditions could or could not ping.
I've filled up with gas and the next guy from the same pump got water and I did not???
If you keep getting problems go with a slightly bigger base gasket to drop the compression slightly, unless your a racer you probably won't feel the difference.

 

[bleedngreen]

Are precut base gaskets available in different thicknesses for KDXs, or am I gonna have to bust out the X-Zacto and start slicing? Also, any ballpark recommendations on thickness would be appreciated.

I'm not a racer, but I do like the feel of a motor with some snap... A little octane booster gets rid of the problem but I'd rather not have to deal with the hassle.

Incidentally, I'm relocating to Spain in August, and it seems the fuel quality there isn't so hot so maybe a decrease in compression is just what the doctor ordered.

cheers, Dave

 

[levert]

I'm not sure on the KDX'S, my wife is the primary driver on it and I have not looked into it.I'm sure there has to be some company like Vertex that does it, on KTM's you have a choice of 3 different thicknesses just for the problem you have.

Good Luck