87 or 91 Octane gas in the KLX?
 

Is it better to have the 91 or 87 octane gas in the KLX? I've asked at my dealer they said 87 because it's better on the spark plug, although I've read only that it doesn't do anything, except help the engine run better and perform better.

I know with all you KLX power crazy people on the forums one of you must all know if it's actually bad or not. If it's good, does it actually help the engine a lot for a better combustion or no differance?

Thanks,

Daren

My bike : 2013 Kawasaki KLX250s - FMF Powercore4, Uni air filter (Soon to have Dynojet kit 2, megabomb, and 351)

I'm sure you'll get a variety of answers. I used to use regular unleaded and was happy with it. However, after I rejetted I noticed a slight stutter between 7,000-7,500 RPMs. I found when I use high octane it all but removes that stutter.

I use 93 in my 09 klx250sf. No science or facts to back up my choice though. Runs great.

If its built for 91 the ignition most likely performs best on 91. 91 is alao better in warmer rides to avoid detonation incase your spark plug gets hot enough to act like a glow plug. I run 87 in cooler monts 91 in the summer

1,000 posts!

I'm going to use whatever grade I have to buy to avoid ethanol.

Higher octane = more MPG, fact! With the 1.9 gal tank I need all the help I can get. LOL I also run the highest in my Honda 1300.

Unfortunately around here ethanol is in all the grades, the only place to get non ethanol is from the bulk plant or a commercial card lock station, and those are few and far in between.

I buy alky free gas, 87 octane. Occasionally 85 from pumps in the higher elevations.

I use 91 octane because it's the only one without ethanol in around here. I also avoid ethanol since I don't use my bike that often and I've also heard some bad stories about ethanol and plastic tank like the IMS.