Hi guys, I have a KLX 300 and am wondering what is the octane level of my gas should be? I have read some that say the premium levels are better, but then I was reading the hard starting fix thread and seen someone say that the low 87 level is best. This was said refering to a KLX 250s. Do the KLX 250s run best on lower levels than my KLX 300? What do you guys use yourselves and what do you recomend for me??

p.s. I hope you don't mind me posting on the 250 forum

 

My KLX manual says minimum octane of 91, so I allways run premium 93 octane. Not sure who told you to run regular, but that could cause pinging/knocking.

btw....mine starts right up everytime, even after sitting for 2-3 weeks in the garage

 

The 250 manual states 91 octane based on one calculation method, comparing that to the method used at the pumps up here its just regular 87.

 

I have been running regular for the past 8 months. This weekend I switched to supreme and HOLY SH*T! The improvement was like converting from 14 tooth to a 13 tooth front sprocket. I didn't know why the bike was so much more powerful at first because I completely smoked my brothers.Today I had remembered that I had used supreme fuel. Shoot, I thought I had become a better rider overnight. I would recommend using a high octane fuel.

 

Yes, I have heard only good things about using premium so far, so I think I'll stick to premium unless someone has some good evidence otherwise!

 

Fuel octane rating has nothing to do with the power you get from burning it. High powered engines use high octane because they are high compression. The octane rating is how resistant fuel is to combusting under compression. Higher octane, lets you run higher compression before getting "knock" which is fuel combusting before the sparkplug fires.....bad bad stuff.

http://auto.howstuffworks.com/question90.htm

 

uhhh ok then what about getting some premium and then putting in some octane boosters from autozone

 

Sure as heck feels like additional power. Try a tank after going 8 months of regular.

I did a little more research and this is what I found "It might seem odd that fuels with higher octane ratings burn less easily, yet are popularly thought of as more powerful. The misunderstanding is caused by confusing the ability of the fuel to resist compression detonation (pre-ignition = engine knock) as opposed to the ability of the fuel to burn (combustion). However, premium grades of petrol often contain more energy per litre due to the composition of the fuel as well as increased octane"

I am guessing that since the bike is rated for 91 octane, and regular is well below that, increasing the octane enables the motorcycle to operate in the way that it was designed? Am I wrong? or did I become a better rider overnight?

 

Gomerpile, I think you hit the nail on the head! If you run the wrong gas in your motor it will not run as it is suppose to. So, you might have actually increased power by using the proper gas for your bike.

 

Before all the mods I didn't notice the difference in gas, but after I do. Maybe I am paying a lot more attention to the bike. Either way, it is great to find a stupid fix to help make the bike wheelie. who knows if it has to do with the fact that I may have just broken in a new tire, or increased octane in combination with the 132 main jet, or if the higher octane fuel has a solvent effectwhile burning cleanerand cleared out the carb. Something happened and it is good.