What octane is required?

[kranker1450]

Back when i raced these beast 20 yrs ago i ran Aviation fuel from the local airport. Cant do that now. lol What is the minimum octane you can run a stock KX500 motor on?

Thanks Tom

[Foxx4Beaver]

as long as it's not pinging/detonating....you can run what ever you want...

I run a 25% VPC12-75% 93pump fuel in all my 2T fuel...with no problems.I could probably cut it down a little more and still be okay.



there's a lot of old threads on here too about octane requirements and what guys like to run....try the "search" option up at the upper left corner of the site.

[kranker1450]

All i can find locally is 93.5. i can order race fuel from one of the shops but not very convenient. I just was wondering what the average min octane was where it started to detonate. I am thinking it is in the low 90's but i cant remember what i ran prior to the av fuel. I think it was 91.

Thanks

[Foxx4Beaver]

yeah 92-93 is typically average,gas stations don't really carry much higher than that(they're far and few between,at least here in the Northeast)....if that's all you can get easily,you can fatten up your jetting a touch if your experiencing some pinging.