Pre mix ratio

[250ex2003]

My bike is almost out of gas so I have to mix a batch. ( I just got it ) I stopped and picked up a quart of klotz synthetic. What ratio should I run? The manual said 24:1 with yamalube. My sons yz85 says 40:1 and that seems like a big difference. The motor im assuming is stock bore. It has open kn filters (no airbox ) pro circuit pipes, boost bottle. Thanks

[Blaster x]

32:1

[RagunCajun]

it depends on mods, jetting etc. on a stock bike or one with bolt ons 40:1 is fine. Im ported and i run klotz 40:1 only. I beat the hell out of mine. 32:1 is fine too.

[bloodmoney23]

go 32:1. the manual really says 24:1........you would eat a plug every 3 min and poopin enough oil out the exhaust youd think exxon sunk another ship!!!!

[firefighterjosh]

32:1 no matter what the mods.

[Glenyzracer25]

I'd go 32:1 if your running it wide open constantly. I run mine close to 50:1 without any problems, but i mainly trail ride and hill climb.

[Dinner]

I run mine at 40:1 just cause I have a 20L tank so it's easy to just dump in half a litre of oil and shake it up.

Bore, mods, whatever have nothing to do with what ratio of fuel/oil mixture to do, As firefighterjosh said...

And for a quick warning, be careful of the boost bottle, they are known for cracking your intake boots, causing your engine to run lean.