110 octane advice needed

[MtnEX]

My quad engine is stock inside.
(a least I hope so cause it would be sad if not)


I have some 110 octane race gas to put in it...
The purpose???....
To rule out weird spark knock as the noise I'm hearing.


Should I drain my tank and run straight 110 to test...
Or should I tame it down by mixing it with the 93 in the tank?


THANKS

[fastredrider44]

I don't think that 110 octane is going to clear up any noise on a stock engine. But If you're insistent on running it, I'd mix it 50/50 with 93.

[REDRIDDER]

Originally posted by MtnEX
My quad engine is stock inside.
(a least I hope so cause it would be sad if not)


I have some 110 octane race gas to put in it...
The purpose???....
To rule out weird spark knock as the noise I'm hearing.


Should I drain my tank and run straight 110 to test...
Or should I tame it down by mixing it with the 93 in the tank?


THANKS I take it your quad is a 1999? has it ever been rebuilt ,because if not the top of the piston could have carbon build up and very well could cause spark knock.

[AZ440ex]

I agree it probably wont make a noise go away unless your jetting is off and your detinating. My opinion is drain the tank. Even if you go 50/50 do it with some fresh gas. It will completely rule out bad gas. 110 straight will not hurt it though. I run left over 110 from my quad in my 450r bike with no issues and it's stock.

[MtnEX]

Originally posted by AZ440ex
I agree it probably wont make a noise go away unless your jetting is off and your detinating. My opinion is drain the tank. Even if you go 50/50 do it with some fresh gas. It will completely rule out bad gas. 110 straight will not hurt it though. I run left over 110 from my quad in my 450r bike with no issues and it's stock.

I think I'll do that... thanks.

[MtnEX]

Originally posted by REDRIDDER
I take it your quad is a 1999? has it ever been rebuilt ,because if not the top of the piston could have carbon build up and very well could cause spark knock.

Oh yeah... it's got carbon on top of the piston for sure.
I've just done one Seafoam treatment... haven't seen how much that cleared out.

It's a 2000... don't think it's been rebuilt... it still has the stock cam and nothing assembly-wise looks touched with a wrench.

[MtnEX]

It wasn't any kind of wierd spark knock, and I didn't think it was going to be because it wasn't like any I'd heard before. I just wanted to try the race gas to rule that out entirely if possible.

I'm running straight 110 octane and it's there from the moment I start up.



Anyways, I've messed with this thing so much I've gotten really good at getting the noise to go away. I just put my thumb on the very tip of the throttle and give it a quick snap-slip.

So it's got to be something about the decompressor mechanism, or the timing chain & tensioner, or the wristpin.