Octane

[sprtrx300ex]

Does running a higher octane gas make you run richer or leaner? What does it do? Is 93 too high for a 300ex?

Thanks

[NTPRacing#19]

93 octane isnt that much diff than 89. just keep in mind that the higher octane you go the thinner the fuel. you wont have to rejet unless you run real high octane fuel like 110 race fuel

[sprtrx300ex]

This is the prob:

Right now my engine knocks. I was wondering if i run 89 if it will stop, or do i have to run 93. There is no in between where i live. I'm going on a trip soon and i need to have the right gas. What do u suggest?

[99'300EX]

not a big difference, it shouldnt matter..i run 93

[frozenh2o]

You don't want to run higher octane than you have to, higher octane=slower burning=less power. BUT if your engine knocks (detonation) you need more octane. You WILL destroy your engine.

Run 93 and listen carefully for the knock. If its still there on a relatively stock motor you are jetted too lean or have the ignition timing wrong. Also possible that you have tons of carbon on the piston/cylinder head, which raises the compression to where it might knock.

This all assumes that your knock isn't something mechanical like the rod bearing, or a worn out piston slapping the cylinder.