[MrSciTrek]

The Update section of my Clymer's manual says that my '05 should be running on 91 octane. ???
(It also has DOT 4 brake fluid listed on the rear brake reservoir.)

That's no prob... but was wondering what changed to raise the octane requirement. Ideas?

 

[Revort]

Similar question: If my bike was jetted I should use 91 too right?

 

[rubix777]

my owners manual says 87 so that's what I'm putting in.

 

[Jkrup47]

i used to run 91+ in my 06.. but the engine design is 20 years old. And there isn't a reason to spend the extra money on something that isn't needed

 

[fog]

Similar question: If my bike was jetted I should use 91 too right?

Wrong. Jetting IE: amount of fuel burned has little or no Effect on Octane requirements. Octane or detonation supression is simply a function of compression and combustion chamber design. There has been no such changes in this area in the EX since it's inseption in 1988. those engines and 07s are happy with 87 octane. Now if you live in Bangladesch or Somilia. 87 octane may mean somthing else. but here in the good ol U S of A you'll be fine.

FOG

 

[Royson]

Does the updated manual say 91 RON or 91 Octane? I know more than a few people mix that up with their new bikes.

 

[Revort]

Thanks fog.

 

[knightslugger]

A 91 RON is equivilant to a 87 PON. PON (or Pump Octane Number) is what we use in the United States. RON is used just about everywhere else and is typically higher than the PON number. MON makes up the remainder and is typically lower than PON. PON is derived from the average of MON and RON, or as you will commonly see at the pump, (R+M)/2 Method.