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Tango
02-20-2002, 10:29 PM
Can someone please tell me where the air screw is on the carb. I looked, but I must be having a brain fart! I couldn't find it! Also, how many turns out is the stock setting? Thanks
02-20-2002, 11:01 PM
it's on the bootm side in the front of the carb. it's not on the bowl but the base of the carb. look under the intake tube to the engine and you'll see it. i think the stock setting is 1 1/2 but not sure
Tango
02-21-2002, 05:44 AM
Thanks a lot!!!
knighttime
02-21-2002, 07:44 AM
setting is 2 1/4 turns out
JB's 400ex
02-21-2002, 10:45 AM
By turning this out and richening the mixture, will this reduce the popping or crackling when compression comes on? That is what it says to do in the latest dirtwheels and I just want a little confirmation. I have changed the main jet up to 155, pilot to 40 and lowered the needle clip one notch and it hasn't hurt performance but it hasn't solved my problem. Any advice?
knighttime
02-21-2002, 11:07 AM
Let the fuel mixture screw stay in the stock position.

What is your problem that your trying to solve?

Please explain.
JB's 400ex
02-21-2002, 02:10 PM
When compression hits, I get a popping or crackling. I have an e-series slip on pipe. Stock filters and everything else. I have upped the jetting and lowered the clip as listed above and it doesn't seem to get much better. Also ever since I put the pipe on, the bike doesn't like to idle. I know they are two seperate problems but any advice is great.
knighttime
02-21-2002, 02:22 PM
First get yourself an aftermarket airfilter and modify your airbox to allow for more airflow. You have the jetting upped, but you have forgotten that the engine will want to suck more air now. Do the above mod and then see where you are at. If you are in the dunes, and an MX racer, get the K&N. If you are where its muddy and wet, get the Unifilter. You must modify the airbox to let in more air.
Tango
02-21-2002, 02:52 PM
I wanted to fatten the carb up for cold starts. From what I understand air screw is for the pilot jet. The pilot jet only kicks in from closed throttle. to an 1/8th open. I'm hoping adjusting the air screw will help with cold starts. I've also made the basic modifications to the bike. I've got the main jet set right, I was just hoping I could adjust the air screw in order not to have to change the pilot. Has anyone tried this? Thanks for your reply!
knighttime
02-21-2002, 03:33 PM
Leave the screw in the stock position and up to a 40 or 42 pilot jet.:D