fcr carb

[450ex]

yeah i got a question for all the people out there that have fcr carbs on their r's...
i have a crf style fcr and am wondering if anyone knows what the jetts in the back of the carb where the air filter connects are for

i going to be running a big bore and am wondering what these jets control and if you have changed them

any help would be apreciatted

[GPracer2500]

Main air jet and slow air jet.

The main air jet provides air to the emulsification tube. Air from the main air jet and the fuel from the float bowl mix in the emusification tube. This aerates the fuel and helps it to atomize when it enters the carb's venturi.

The slow air jet provides the air for the pilot circuit. The fuel for the pilot circuit is provided by the pilot jet (also called a slow jet).

You probably won't have to touch the air jets unless you're having problems getting the right air/fuel mixture through more common jetting procedures [shrug].