I read in a mag that the recomended octane for the Raptor is 87. Does anyone know if this is a good thing or should I use higher. I put 94 octane in my 400EX and it runs like a champ, so I'm thinking it should quench the thirst of the Raptor also.


2001 Blue Raptor
2000 400EX

 

Usually the need for higher octane doesnt occur until afer 10:1 compression. raptor has 9.2:1
Personally I will use 92,93 in a two stroke but in four strokes i think it is less important because if it is good clean gas there usually isnt any engine knock. In two strokes I seem to think it helps burn the oil off a slight bit more, But that is just a thing I do, just like using synthetic two stroke oils, I think it has helped with longer times between rebuilds. Modifications that increase compression always require high octane gas though. And sometimes it just comes down to the pocket book. With 92/93 octane nearing $2 a gallon sometimes it just is not worth the money.

 

Contrary to popular opinion, the higher octane will not produce more power as long as the engine doesn't have so much compression that it is detonating the fuel. Race gasoline isn't more potent, so to speak, but what it does is allow you to run higher compression which does produce more power. The lower the octane, the more "explosive" that the gasoline is, therefore actually providing a marginal increase in power as long as your engine operates correctly with it.

With the Raptor's listed compression, 87 octane would probably be the best fuel to use in it. You probably wouldn't notice a lack of power if you use a higher octane gas, only a loss of extra money that you pay for it.