jetting......whats right?

[cals400ex]

i have a 400ex with a twin air airfilter and a modded air box lid. i rejetted the carb and can not tell a difference. i first went up from a 148 to a 150 and then to a 152. i can not tell a difference with the jets. the plug reading all look very similar. is this telling me i need to go up more because the bike is still not cutting out on full throttle. i would not think i need to go richer but who knows. any help would be great

[Wheelie]

Don't jet up until the quad cuts out on the top end. Either the 150 or 152 that you're using should work great with the setup your describing. If you're concerned about the bike running too lean, use the 152 and turn the mixture screw out 1/2 turn from it's current position.

Good Luck!

[cals400ex]

i already have a 42 pilot jet so that should be fine. as for the main jet i can not tell a difference with the 150 to 152.